Severe Pain After Sex

So last night after we had sex, I ended up having the worst pain/ cramps. I could not even walk. I curled up in bed crying &, I was so nauseous on top of it. I forced myself to lay on my stomach & had my leg in a position it was next to my stomach/on the side. The pain lasted about 5 to 10 minutes. This has never happen before. I mean I've had some discomfort during sex before but never severe cramps like this. It almost felt like the pain I endure during a miscarriage. Any ideas what could have caused the cramps?