Issues with my body

So I'm on the depo shot and haven't had my period for months and out of nowhere I'm spotting. I worked out today but I go to the gym every other day and have never done this. I'm also cramping. I've been on some antibiotics for a virus I had and I've been having unprotected sex. My boobs have also been leaking something for the past week. I don't know what is going on with my body. And normally I do. I've also been super nauseous. Anyone know what this could be? TIA