As fully functional human beings, we shouldn't really exist. The probability of you coming into the world exactly as you are is about 1 in 102,685,000 - that's what it took for the right sperm to meet the right egg at least once a generation all the way back to our single-celled organisms. So when you think about it, it's a wonder that most of us aren't riddled with strange physical ailments, when you consider the odds of all the things that can go wrong with the tiniest tweak of your genetic code.

But sometimes things can go wrong, and not always in the ways you'd expect. From sperm swimming backwards to your skin turning blue, here are some of the weirdest things that can happen to your body.

Bones in the ear canal

There's a reason why swimmers and surfers are advised to use special earplugs, lest they want their ear canals to close up with bone. This condition is called exostosis, which means abnormal bone growth on the surface of an existing one. When this happens in the ear canal, it's called 'Surfer's ear', because it's caused by irritation from cold wind and water.

If left untreated, the condition leads to decreased hearing, as well as more ear infections and pain due to improper draining of the ear canals. According to some studies, most surfers who don't protect their ears have at least a mild version of this problem.

Sperm goes the wrong way

So, normally during an orgasm, a man's semen spurts out of the penis via an opening in the urethra. But in rare cases, the stuff doesn't make it out, leading to what's known as a 'dry orgasm'. In medical terms, this is called retrograde ejaculation, and it can happen if the sphincter that shuts off the entrance from the urethra to the bladder doesn't work properly. In these cases, the path of least resistance for the semen is actually to go straight to the bladder, rather than make its way out.

Retrograde ejaculation can happen due to prostate issues, high blood pressure, or nerve injuries. The bladder is also where semen ends up when men use the so-called 'squeeze technique' to prevent ejaculation. Thankfully, the condition is not dangerous, and is usually only treated to help with fertility issues.

Your bum falls out

That's really the most straightforward way to describe this. A rectal prolapse refers to the situation when the walls of the rectum - the last 20 cm of the large bowel - lose their internal attachments, slide out of place, and partially or fully come out of the anus. It may seem horrifying and funny at the same time, but you don't want this to happen to you, because it's described as painful and extremely uncomfortable.

For treatment, the rectum basically needs to be pushed back in there and stitched into place via surgery. Causes of a rectal prolapse include straining too hard to poop, but it can also happen thanks to childbirth, or you can simply have a genetic predisposition to it.

Your nails peel off

Surprisingly, this one doesn't hurt as much as you'd think. The problem is called onycholysis, and it refers to the nail detaching from its bed, usually starting at the tip. Onycholysis tends to happen gradually and without much pain, and can be caused by many things, including yeast, bacterial, or viral infections; certain drugs; overzealous manicuring; allergy to nail glue; and psoriasis. It can also happen due to trauma, which is why you really don't want to slam your fingertips into doors if you can help it.

The good news is that nails grow back, and as long as you can avoid or fix the cause of the detachment, the condition will be gone when the damaged nails grows out.

You turn blue

Even though Smurfs are thankfully just a figment of some Belgian cartoonist's imagination, in real life, it's possible for a person's skin to turn a deep, unnerving shade of blue. The medical name for this skin condition is argyria - from the Latin name for silver, "argentum". It's caused by too much exposure to silver dust, or prolonged ingestion of silver salts, which causes tiny brown-black granules to deposit in the skin, particularly around sweat glands.

Those afflicted are usually workers involved in silver mining or silverware manufacturing, but it can also happen to people who believe in taking dangerous colloidal silver supplements - an alternative medicine product with no proven benefits. Usually, the human body contains around 1 milligram of silver; if that amount exceeds 5 grams, this can be enough to cause argyria. Treatment options are extremely limited, although there has been one successful case of treating argyria with lasers.

So you might be having a crappy day, week, or even year, but unless you're really unlucky, you can at least by comforted by the fact that your sperm is swimming straight, your skin isn't blue, and your rear end is firmly attached.