Cramping after intercourse

Moe • I am 37 yrs old. Had my son in oct 2016. My first born is 13 and just had my daughter in dec. I am a black belt in Bjj and love muay Thai and CrossFit.
Has anyone experienced this yet? After our "sexy" time, I had the worst cramps and ended up in the fetal position for 5 mins afterwards. 🙁 that was not fun.