Pregnancy symptoms, on depo

So 5 days ago my bf and I did it and he finished inside, and he thought since I'm on depo we should be fine(first month on depo), well now I'm not feeling good I'm feeling nauseous and I have cramps and I had some brown spotting today, but my nipples are dark but my boobs don't hurt. I'm really worried should I test next week? Please help.