Bleeding after sex

Kaycee
Hi everyone. So I've been sexually active for about 3 years now and only recently I've been bleeding every time after I have sex. My period is regular so it's not that, my ex partner was a virgin so I don't have an infection and my now partner of 2 years was also a virgin before we had sex and doesn't have any infections. I've had the Mirena in for about 2 1/2 years and haven't had a single problem with it.
So I'm just looking for some insight as to why I'm bleeding every time after sex.