It's 9 o'clock on a Friday evening in Sears. An elderly lady admires two different dresses that she has no intentions of buying. The cashier in the men's department counts bills from the register. In the dressing room, in the last closet on the left, two nervous lovers are fucking as awkwardly as nine square feet of cramped Sear's department store space allows. The man, a true thirty second stallion, grunts with his final thrust, and the woman desperately tries to remember if the beginning of their tryst involved any kind of contraception. Bottom shelf whiskey never mixed well with her anti-psychotic medication. Warm seepage down her thigh tells her all she needs to know, and the worst part is that she isn't even sure if it was a worthwhile lay.
The woman yanks away, grabs the curtain, and wraps it around the man's neck for not pulling out. But it's too late. The sticky, snot-like web of spunk has flooded her lady parts. It contains millions of squiggly little tadpoles with bulging heads programmed to penetrate. They try to fertilize the first thing they see, which happens to be a colony of Chlamydia cells. A few squigglies make it to the womanly tubes though, risking the worst sexually transmitted disease of all: life.
These two lovers were your parents.
Did you just think about your parents having sex? Gross. You need help. 
If it weren't for the handicapped stall your parents found in a remote corner of that summer beer festival on their second date, you wouldn't be here today, trying to hook up in regular size port-a-potties at the same festival. This is why you were a mistake.
Have you ever wondered what you're doing on this Earth? Not in a philosophical, existentialist way, but in a why-didn't-your-mother-shank-your-fetus-with-a-broken-beer-bottle way? Well, your mother often wonders the same thing.
Chances are, you were probably an Oops Baby. Maybe you weren't actually conceived in a Sears dressing room. Maybe it was a port-a-john at a flea market or the walk-in cooler at the Dairy Queen. Whatever the location of your parents' fuck fest, you were an unwanted side effect.
Sure, your parents say that they love you. They also told you that smoking would make you popular, even though they knew you'd never be cool. Parents lie. If you still believe mom and dad didn't slit their wrists after reading the pregnancy test results, consult my list below. If you meet any of the following criteria, you were probably an Oops Baby.
You are Catholic.
God wants us to fuck to make babies. Duh. Why do you think impoverished Guatemalan peasants have thirteen kids? Obviously God wanted most of them to end up in the human trafficking industry. Condoms kill babies. It's in the Bible, look it up. Right next to the part that says you have to slaughter a goat if the whore you hire turns out to be your daughter. So if you have seven siblings, it's pretty clear: you may have been part of God's Plan, but you sure as hell weren't part of anybody else's.
You were conceived circa 1989.
Skid Row released "I Remember You" that year. Car windows across the country fogged up to that baby-making ballad. Unfortunately, everyone was too horny to remember to use a condom. Sure, other hook-up songs have vibrated the radio waves before and after "I Remember You," but I haven't had to grow up with the results. As someone who was conceived in early 1990, I can tell you, a lot of the people my age are mistakes. (I come from the generation that is giving Ke$ha a career other than C-list stripper.)
You're adopted.
Your mom didn't abort you, but she obviously didn't want to keep you. She sold you on eBay, where your fake mother accidentally bought you instead of an Aeron chair. She kept trying to sell you back, but every time she just ended up with another box set of Joanie Loves Chachi. Finally she just decided to keep you for the easy tax exemptions. Then she realized it would be cheaper to just outsource you to the Indian family down the street. If it makes you feel any better, your fake mom kinda regrets getting rid of you. (Note: this only applies if you are a cute Congolese baby and your mom reads People.)
People think your parents are your siblings.
Your mom was captain of the cheerleading squad and your dad was the star quarterback. (Accidental pregnancies only happen to beautiful white teenagers.) Things got a little hot and heavy in the back of the school bus, and nine months later, you popped out. Luckily the cheerleaders were able to incorporate you into their routine. Every time your mom shot you from a cannon into the crowd, she hoped one of those sloshed fans would keep you.
People think your parents are your grandparents.
Guess your mom's violent mood swings and various fender benders weren't the result of menopause, just the result of her being a woman in general—a woman who's shriveled ovaries weren't ready to give up for some reason. Too bad your dad didn't know that when he shoved his naked penis inside of her during a boring PBS phone marathon (a true sign your parents were already too old to have kids). If you repeat their mistake and have children of your own, you'll not only be changing your baby's diapers, but your parents' as well. At least you can just plop them all into the playpen together and see which ones are still alive at the end of the day. Or shut them all up with some chloroform. Too soon?
Fortunately, you can stop the cycle. Even though you're a mistake, you can prevent more from being created. Please, refrain from procreating if you meet any of the following criteria: you think "irregardless" is a word; you watch Jersey Shore; you plan on sleeping with a cast member from Jersey Shore; you have a tramp stamp of the confederate flag; your name is Casey Anthony.
In the meantime, you can try to convince your parents that they were right not to abort you. Or to have gone to a nursing school dropout with a rusty pair of tongs. Prove to mom and dad that keeping you wasn't a mistake. Continue to pursue that art history major of yours. Those piss stained tuition checks definitely won't have your parents longing for the days when you were just a fragile little fetus, vulnerable to accidental falls down the stairs.