Tested Positive For Chlamydia, Taking Birth Control Shots, Stomach Ache, Running Nose. Is It Because Of STD Or Shot Or Just Flu?

Hello, these past two weeks have been crazy for me. About a week and a half ago I went to the doctor for what I thought was a yeast infection . I had a pelvic exam and waited for the results. The next day I had sex with my boyfriend and the condom broke, I went straight to the pharmacy and bought plan b. I had no side effects from that. The next day I was contacted by my doctor that I tested positive for chlymidia. I immediately went and got the medication for that. Each time I ve taken it I feel a tiny bit nauseous but nothing enough to bother me. A few days later I went back for a check up and started bitch control and got my first gardasil shot. It s been 6 days since then. About three days ago my throat started to feel weird and I had a very runny nose. The next day I wasn t even able to get out of bed, my skin was achy and I didn t feel good at all. Today I woke up feeling okay, just my runny nose. I took my birth control at 10:30 and my std medicine at 11:30 shortly after my stomach began to hurt. It s not 5:48 and I feel the need to vomit . I can feel it in the back of my throat and I m in tears I feel so sick. My question is what is this? Could it have to do with the medicines I m on? Side effects from the pill, or the shot? Or is it a cold and stomach flu?