I know this is TMI but last night I was having sex with my husband and I was on top and on the left…

I know this is TMI but last night I was having sex with my husband and I was on top and on the left side of my tummy next to my belly button I felt a cramp almost like if baby girl was pushing on my tummy really hard and now when I press on that area that hurt last night it feels a little sore, what could that be? Was she actually pushing on me? Or was it just the round ligament pain?