So I just got off bc shot in December my last shot was in October of 2016 had a slight period Feb 6 witch lasted 4-5 days and was supposed to be ovulating the 20th of Feb and had unprotected sex well I had spotted March 5 and like one more time after that not sure what day took a few different hpt all was negative. Have a doctor's appointment on the 1st of may . Could I be possible pregnant? With a low hcg