Okay, So On September 24th Me And My Boyfriend Were

okay, so on september 24th Me and my boyfriend were dry humping naked, but I made sure his penis tip was nowhere near my vagina and it only lasted like 10 seconds so he didn't have the chance to ejaculate or pre-ejacute. 2 days later I had my period, but it lasted 5 days, when it usually lasts 7 days, also on october 13th (the first day of my fertile window) I played soccer and started feeling cramps while playing, when the game finishes I went to the bathroom and saw a little amount of brown blood but it stopped the next day. could this be implantation bleeding? could I be pregnant? I'm feeling very weak right now and my hands are cold and I don't know why.