I have been sexually active for 3 years. My boyfriend and I were fooling around the day after I believed my period officially stopped, it had been about 6 days and I had not bled all day. He began to finger me and when he pulled out, noticed his hand was covered in blood. We cleaned up, had sex, and there was no blood afterwards. Was the blood period related or could it have been my hymen? To my knowledge, I can't remember it ever breaking.
It was likely left over from your period.