**TMI** pain after bd

My husband & I bd'd lastnight in the shower.. And it hurt a little not sure if it's because we haven't did it in a week or two. But this morning I woke up and my left side was hurting and I feel a lot of pain/ pressure in down there.. 
Has this happened to anyone else?
What could be the cause of it?
I am in my fertile week so not sure if that has anything to do with it.