Confused

So since the 23rd of April I've had 1-cramps,2- headaches,3- spotting,4- lower back pain,5- tender breasts that feel like they are trying to lactate,6-nauseous and actually threw up 3 different days now,7- I'm on the shot. Is this normal when the depo is leaving the body. Also everytime my boyfriend and I have sex it's never with a condom and he always cums inside of me then stays there for a few. Could it be possible that I'm pregnant?