An hour bleed during sex?

I'm stumped. I last had my period on the 28th of august. It lasted 7 days(never that long normally 4 days at most) then on the 17th of September which would be a week early or getting my period, my hubby and I started to have sex but It was gentle we JUST started and I bled all over and was so confused I thought wow my period just started put a tampon in took it out in the am there was nothing on it and haven't had any bleeding since its been 5 days. Has anyone had this happen? Could it have been implantation? A cyst? Pregnant? So lost for answers. My period isn't due now for 6 more days.