Im 21 years old i have no sex drive.ive been on birth control for 5 years. whats wrong with me?

Normal: It can just be that you havent met a person who you are ready to be intimate with or you may actually have decreased sexual desire because you have some condition such as depression etc. See a doctor if you think it's a problem and talk things out. A detailed history can help tease out the cause of your lack of sexual drive.

The pill: Your problem is quite common for women on the pill. Birth control pills elevate shbg, a protein that binds to the testosterone in your blood. This decreases the effect of that testosterone, which lowers the sex drive. One option is to change to a non-hormonal contrceptive. Another effective option is to take supplemental testosterone - you would need to see your physician for a prescription.