Allergic to Semen?

I’ve been with my boyfriend for 7 years and I’ve on birth control for half our relationship.

SOMETIMES, I let my boyfriend finish inside of me. I’m in the birth control and I’m comfortable and confident things will be okay.

The issue is that whenever he cums inside me, I am always in INTENSE, BURNING pain afterwards. Like to the point where I need to put an ice cold washcloth on my vagina for a bit and even then, I am very uncomfortable afterwards.

I have no idea why this happens! This doesn’t happen when he pulls out, only if there’s minor friction from lack of foreplay (we have minimal time together as we both still live with our parents).

I recently had a pap smear and was checked for STIs, but I was cleared. Unfortunately, I forgot to mention this to my OBGYN.

Can you be allergic to semen? Has anyone else experienced this? I feel like the only one.