I am 19yrs old, not pregnant and not fat but still i have swollen veins in my leg.what should i do?

It's up 2 u: It is likely varicose veins. If they are small, or large, and do not hurt then you have to do nothing. You may be focused in and overly critical if they are small. If they are truly bothering you there are physicians who can inject them with chemicals to sclerose ( destroy) the vein. It is usually done by vascular surgeons but look up vericose vein treatment and consider that option. Good luck.

Leg veins.: You should see a vein specialist for a venous evaluation. Depending on the types of veins you have an ultrasound of the veins could be indicated. There are many types of vein treatments and a vein specialist can give you the options.