Welcome! I 2nd what Denise said with one addition. Have you tried any antacids like Malox chewables when you have an attack? I personally don't have any luck with tums or rolaids, but the Malox chewables are larger and crumble easily. This seems to me to absorb the acid and coat a bit better. Since the prilosec helps it sounds like reflux and I have had the pain in the same spot as you. If you take an antacid and it helps faster you are even more likely to have reflux. Spasms are very painful and GI docs do have a few meds to help with them. Like Denise said, I'd get an appointment with a GI doctor soon.
Nissen 6/06 and 5/09