I bleed for 34 days straight

Okay so I went on the injection so I wouldn't be able to get pregnant... I was fine pretty much the first month and a half then bleed and bleed I was having like full on periods but sometimes I wasn't then after say sex I would get it again and I was like wtf! My bf doesn't mind because he understands but my period just stopped... after the injection wore off! I'm kinda swore and itchy there and I'm not sure if it's because I let my hair grown out abit which normally I shave ever second day or if it's because maybe it's irritated because of how many tampons I have used... because I'm still using them just in case and it's only been two days. I'm scared I may be infected or something but I do sometimes get like this but it's different like itchy but then my clit is swore to touch....

Any ideas? I'm scared