is this because of the depo shot and plan b?

Ok, so I had sex with my new guy on Nov. 12. I took plan b the next morning. I did feel a little sick afterwards but nothing I couldn't handle. So on Nov. 26 I got the depo shot. I still felt kinda sick but not too bad. This week I'm getting very painful cramps, very bad nausea, sharp pain on my right side and some pain around my belly button (enough that it hurts if I have to bend down). Could this be because of the plan b and the depo shot together? Or could it be something else? It's hard for me to get an appointment with my doctor (that's why I had to go to planned parenthood for my depo) and if it's because of the plan b and the depo, then I would prefer not waste my time going to the doctor. I was given a pregnancy test before being give the depo shot and it came back negative.