Advice???

First let me start by saying that im on depo....Okay so I've been experiencing some crazy things lately with my body ...going to restroom more...I'm eating way more....my period is brown one minute then bright red the next ...I'm starting to cramp and I have never cramped since I've been on depo...NEVER.... But now I'm cramping...my breasts hurt but I think it's because they are growing ...ive been having weird periods well at least I think it's my period and not to mention I've been tired more and more every day . I don't want to over think anything because I am on birth control but this doesn't seem right.... I took a test like 2 weeks after I had unprotected sex and it came out negative but I think I need to take another one because it's been a month since then. If you have any advice or information that may come in handy please ladies let me know.