Is this ACNES?

Hi everyone,

My GP and physiotherapist independently mentioned the possibility of ACNES, and I'm currently waiting to be evaluated. I'm not looking for a diagnosis here, but I'm wondering whether anyone with ACNES recognizes this particular symptom pattern.

For about four years I've had a recurring sensation in my upper abdomen. The best way I can describe it is that it feels like a small balloon slowly filling with water. I can actually sense the build-up happening, and then there's a distinct "thump" or contraction, after which it immediately starts building up again. Sometimes this happens every few seconds, sometimes every minute, and sometimes it's barely there at all.

The location is difficult to pinpoint. It often feels around the xiphoid/upper abdomen, but sometimes I feel it more above my navel, and afterwards I often develop soreness under my left rib cage/diaphragm area. During a recent episode, the "thump" seemed to originate above my navel, while later the left side became sore.

The symptom seems to be influenced by posture and activity. It often becomes worse after sitting for a while, after driving, or sometimes after a nap. Pressing firmly above my navel once seemed to reduce the thumping temporarily.

One thing I'm unsure about is that I don't have one obvious fingertip-sized tender spot. Instead, I feel like I have several sore areas around my upper abdomen.

Has anyone with confirmed ACNES experienced something similar, especially the rhythmic "build-up → thump → build-up" sensation? Or does this sound unlike your experience with ACNES?

Thank you!