Depo Shot?!?!

Okay so after two months of thinking, I've decided on getting the Depo Provera shot because of problems with my body, period, etc. I think this is a good idea, especially after constant reassurance from a health nurse but I'm still not 100% sure.

I just want some honest opinions before I make this decision. I've been on 4 different types of birth control pills for a year and a half and none seem to work for more then a few months.

I can't do it anymore, especially since I'm sexually active with my boyfriend and have had two pregnancy scares since we started having sex. So yeah just opinions and girls who have been/had been on the Depo please!!