Im on combination birth control pills and im worried I might be pregnant. My last period June 18,2016 and since then I have had sex multiple times but then I started having pain in my ribs and pain in my back and chest pains. I ran a low grade fever for 2 days and had headaches then went back to normal. I look bloated, I feel constipated and now I have sore nipples. I'm expecting my period to come July 14 or 15, 2016 but now I'm experiencing what I think is a yeast infection, like the one I had before I got my last period. I have taken 3 negative pregnancy tests since my last period. I'm not sure if these are signs of pregnancy and I'm sure what my next move should I be??? Do I keep buying pregnancy tests ??? HELP PLEASE .