Rib/upper abdomen pain

I was woken out of my sleep this morning by a burning (almost searing) pain right under my rib cage, at the top of my abdomen/uterus. It was mostly on the right side, but did radiate a little bit across to the left. It was pretty uncomfortable. I am tough when it comes to pain but I’d say it was moderate. It seemed to calm down a bit when I propped my back up with a pillow and sat more upright. Any one else experience this? From reading a little online it seems like it may be either pressure from the uterus expanding and pushing the organs up under the rib cage, or the baby pushing and kicking the ribs. I have been experiencing acid reflux pretty bad the whole pregnancy, so it may be related to that? Although this is a completely different location under the ribs.