Severe stomach /anus pain after sex

My boyfriend and I had sex with protection but the condom broke which cum got inside me …After we had sex I went pee and a few minutes later I started having severe stomach pain above my belly button and below plus my anus started throbbing

I started getting super nauseous and light headed and felt like I was going to pass out

My stomach started getting super hard and it felt like horrible cramps/gas pain and tbh contractions

I was finally able to go to the bathroom but I still have some stomach pain and I’m super nauseous

I read on the internet semen allergy is a thing and common …some ppl get hives ,itching and some get GI issues which is what I’m having atm

I’m in so much pain

Has anyone experienced this ?

This is so embarrassing but i just don’t know what to do 😩😩