Hi I'm 24 years old my left pupil is bigger than the right. I noticed this about 10 years ago. I don't have migrains, but one eyelid dose droop. My vision isn't as good in my left eye and I wore glasses when I was 10.. It dose concern me it is rather noticeable.. help?

GO SEE A DOCTOR ASAP!

Drooping eyelids and change in pupil diamater are signs that something could be seriously wrong. From what you describe it could be Horner's Syndrome which itself could be caused my a wide variety of things each affecting the sympathetic nervous system the causes could range from something simple like a congenital defect present from birth to a brain tumor (which usually does not cause headaches until it's too late). I don't mean to scare you but these are normally considered serious symptoms.

Do NOT put this off, it is important that you see your doctor soon.