Implantation cramps?

Ok so I had unprotected sex during my ovulation cycle. Last time I had sex with 2 days ago. Today is my highest day to get pregnant. I just woke up out of my sleep with horrible painful cramps (it’s 3:30am here). Which never happens. My first pregnancy I had really bad cramping in the begin of my pregnancy - even back cramps.

Do you think this could be implantation?