Bloody discharge on depo

Hey guys I need some feed back! I’ve been dating someone for the past two months and we have unprotected sex pretty frequently because I’ve been on depo for the past two years and have never had a single period, I do feel comfortable having unprotected sex so I do. That is not the issue at hand, yes I know it’s not 100% safe i am completely aware, however three days ago I started to have bloody discharge, it started really dark with an odd smell then has gradually lightened up in color and occurrence. Since I know it’s not ovulation due to my lack of menstruating, I’m wanting to know if anyone has experienced the same or knows why this could be happening besides pregnancy.