Period weirdness after sex?

Ashley

Okay so my period is normally 4-5 days and is only heavy for the first 2 and rarely 3 days. I had sex with my boyfriend recently (losing my virginity besides being raped when I was a young teen) I got my period a day late which is fine but the weird thing is my period is still heavy after 5 days. This may sound like a dumb or weird question but could sex have made it different or is it a weird coincidence?