Spotting from sex?

Kaley

Earlier my s/o and I were doing it in the shower and it was really hurting my cervix so we stopped. I started to give him head and tasted blood and when I wiped with tissue it was a bit pink. I haven’t had sex in a week and the guy is pretty well endowed but we’ve never had this issue in 9 months except for once a couple months ago. I’m supposed to start my period in a couple of days but it’s unusual for me to spot from sex so I’m worrying about what could be causing it