Hello. I Woke Up Last Night W Sharp Pain Around

Hello. I woke up last night w sharp pain around my right ribs, right side chest and right shoulder. It hurts when I breathe, especially if I try to take a deep breath. I got up from the pain, and assumed it was gas. I ran for a half an hour and it was fine. But about a half an hour later I laid down just to check emails, etc and the pain returned and hasn't stopped. I took some Tums. They don't seem to be helping.
As background, although I am pretty active I am obese: 5'2", 215 pounds. But I've been active my whole life. I gained weight after being diagnosed w epilepsy 6 years ago. I have been seizure-free for almost 5 years.
I am dealing with a lot of professional and personal stress. I feel like it's probably nothing to worry about (the chest/rib/shoulder pain), but it is awfully painful. Thoughts?