Pain in upper/mid left abdomen for 5 days...

My bf has been experiencing occasional severe pain (but not “burning” or “sharp” pain) in the upper/mid left abdomen for the past 5 days; it doesn’t seem like the intake of food is triggering it, and it comes and goes. When it comes, he has to drop everything and lay down…I’m starting to get worried but he refuses to go see a doctor since he has no insurance at the moment. Any ideas of what might be causing this?
Any advice would be greatly appreciated!