Pain during sex?

So sex is usually fine for me, however it's been getting worse for certain angles. Missionary when I put my legs up gives me a dull stabbing pain, and even last night when he was fingering me I started getting a weird pain (which was a first). I would say it's more uncomfortable than anything but there are times when I yelp from it  being so strong. Maybe he's hitting my uterus/bladder?