Period Sex

Okay, so I’m on my period & my flow was starting to get really light to the point where I could go a whole day with a pantyliner so I had sex with my boyfriend. When I got home I went to the bathroom & when I wiped I noticed that I had bleed a lot. But I had only bleed a lot there sitting down on the toilet. I put a pad on and went to bed but when I woke up to use the bathroom again my pad completely clean, I sat down did my business & again there was blood. This has never happened to me, any advice or similar stories?