“What happens if I wear contacts too long?”

The most severe complication with contact lens wear is infection specifically corneal ulcers which can can lead to blindness. Overwear can also cause vascularization of the cornea (blood vessel growth)

It might sound gross, but it's the same as wearing your underwear too long! Your contact lenses are floating on the tear film of your eyes. As time passes, the lenses are coated with proteins, bacteria as well as debris from your tear film. The longer you wear your lenses without cleaning them, the more gunk will coat the lenses. For some people, they will form a reaction to the protein on the lenses, and become unable to wear contact lenses at all. You can also get bad infections from the bacteria that coat the lenses. So, you should only wear your contact lenses during the day, not overnight, and the lenses should be cleaned or for daily lenses discarded. Hopefully, this information is helpful.

You may deprive your central cornea of oxygen and it will start to painfully break down.

You risk extreme dryness, red eyes, new vessels growing onto your cornea and possibly eye infections