Hello. I Am Scared That I May Be Pregnant. I

Hello. I am scared that I may be pregnant. I ad sex on the 26 of March. I took the emergency contraceptive the Saturday afterwards. About 2 weeks after I took 2 pregnancy tests. Both came back negative. I still did not see my period. I waited another 2 weeks before taking another pregnancy test which came back negative. I was experiencing what seemed like menstrual cramps on April 30, 2015. I saw a bit of blood starting from May 2 - 7, 2015. I haven't seen anymore blood since and the pains had stopped. The blood flow was light. On May 15, 2015 I took another pregnancy test which came back positive. Is it possible that I might be pregnant after all that?