Thanks all. I am ashamed to admit I got my brother, who is a vet, to ultrasound me to look at the lumps. There was nothing of note there, but the contents of my bowels were churning like mad (anxiety related IBS, i guess). Anyway, bro said lumps would either be poo, or the bowel wall itself contracting. He told me to stop being such an idiot and get a grip. He's right.