help help I'm scared

Okay so I've been on birth control for three years and haven't missed a pill in months. I had sex on the 29th of april with a condom and he pulled out. It was for about a minute since we hadn't done it in a while. We checked the condom and filled it with water and we did not see any hole and he put it on correctly. The day after, may 1, I started to wipe and I saw light pink/ brown. This continued through May 2 when I started antibiotics for sickness and the bleeding got more red and a little heavier Now it is may 3 and I am experiencing the same spotting. I'm really scared I could be pregnant. But we were really safe!! Couldthis be implanation bleeding or me just getting my period. As of today, I am supposed to get my period in 8 or 9 days. Please help!!