I am a 20 year old active female. I have been on my period since nov. 2, my period has never lasted over 4days. I have not been sexually active since my last period, and I am really starting to worry. I was on depoprovera birth control shot. But I think 16 days and looking like its not even close to ending is probably not a good sign. PLEASE HELP! I really don't have the money to see the doctor right now, so if anyone knows what could be happening I would appreciate all advice! THANKS!

Some people will have excessive bleeding while on depo provera... others go the other extreme and their periods stop. In most cases, the bleeding is more of an annoyance than a real concern.
If you can't actually go into see your doctor just yet, how about just calling the office and letting them know what is going on. They may be able to give you some peace of mind.

Forgot to add... a response to the depo is far more likely than premature menopause. Quite rare for it to start in someone so young.