15wks 5days and feeling small sharp pains like cramps underneath belly button

Ariadna • 23 years old. Expecting first baby 👼
Ok ladies I had cramps early on in my pregnancy but today I had them and as I was laying down on my side they got worse .. They where sharp pains in my lower abdomen. I laid on my back and it seemed to ease it but my lower abdomen is tender. I was thinking maybe because I had sex yesterday but it's never happened before . Anyone feeling that ?