Wow. You have no idea how happy I am to find this place!! I thought I was alone in my situation! I can totally relate with all of you guys! There were so many posts that I read and it was like I was reading a story from myself that I didn't know I posted! Seriously! Your experiences and anxieties are spot on with mine.
My story goes like this:
I served as a missionary for my church for two years in South Korea. Never before in my entire life did I have anything like this. Before going to Korea I went to the Missionary Training Center (MTC) in Provo, Utah. There I had to learn the basics of Korean and how to teach the gospel in Korean. As practice, we would teach in Korean to strangers who volunteered to listen. These teaching episodes really stressed me out, and I began to notice that my bowels/stomach were reacting to the increase of stress.
When I finally got to Korea and in the "real world," lessons with people were next to unbearable. Even though I couldn't speak Korean and thus, didn't have much responsibility or have to contribute much in the lesson, I was still stressed out. I remember this one lesson (by lesson I mean meeting with someone who is interested in learning more about the church and talking about it) I was in and out of the bathroom five times. Luckily, as a missionary, you have a "companion" who you live with/teach with/travel with, etc. who could keep teaching as I was on the can.
The condition began to get worse and worse. I wasn't really scared that it would happen, but it was definitely uncomfortable and it did happen a lot. I became scared of it happening later on... I was at a large meeting with other missionaries listening to some speakers after we had a big lunch. I was really stressed that I might get called to get up and say something in front of them. I felt pressure in my stomach start to build, and then subside, then come back bigger, then subside. Finally it got so big and growled LOUD and LONG!!! It was the worst I'd ever experienced in my life!! People in the front row looked around (some laughed) and everyone around me gazed at me. I played it cool, and a minute later slipped out to the bathroom, but I was soooo mortified. I asked a friend who was sitting a few people away from me if he'd heard it. Not only did he hear it, but he felt the bench shake. He said he "thought it was an elephant dying." LOL!! I can laugh now, but then it was horrible! I think that was the pinnacle moment when the whole thing became a phobia.
So now, here I am in college and I've missed quite a few classes because of the fear of this happening in class. It's really sad, really sad. I've seen the doctor and had blood tests (this isn't a parasite from overseas he says) and I've changed my diet quite a bit, but still, it'll happen here and there. The second most tramatic experience was I was at the theatre and there was a really pretty girl from one of my classes. I said hi, we started talking, i sat beside her for the show and sure enough, I was sooooooo scared that my stomach would make noises (it was a small quiet, drama theatre) finally it did, and it was really loud. She looked and me and kinda chuckled, but I was so embarassed. Everyone else would have heard it too because it was so small and so quiet right when it happened. I'm surprised the actors didn't burst out laughing!!
So then I had to watch a SECOND play and right a review on it as an assignment for the drama class. Before I went I was horrified. I was so scared of it happening all over again like it did with the gorgeous girl beside me. Even walking to the building, as I approached it, it was like in slow motion and really depressing, like I was about to be incarcerated in this tiny theatre. I sat at he very back in the middle, with the aisle right in front of me so I could stretch my legs and be comfortable. I took my jacket in this time (passed the coat check) and wrapped it around my waste to stifle some noise in case it happened. As I was sitting there waiting for the play to begin, I was feeling nervous, but not bad becuase people were coming in and they were talking and stuff. But then the lights dimmed and I just thought to myself "Oh God..." As expected, the noises came. They were loud, like when all the water in the toilet has just been flushed and it makes this rapid sucking noise. That's what my stomach was doing. Luckily the play was loud too and my coat helped, but my heart was pounding and my legs were literally shaking. I had to pass gas (padded seats, thankfully! and there was some big guy beside me so he can take the blame) A LOT. Finally intermission came and I left. Watching another hour and a half of it would have been pure torture! I felt so free when I ran from the building and all the anxiety/discomfort instantly disappeared.
I too can ~feel~ it in my stomach sometimes, like when it gurgles, I can feel it bubbling on my left side like some of you have mentioned.
Finally, I've been thinking about some of the stuff I learned in Psych 110, about self-fulfilled prophecy, biofeedback, situational anxiety, that sorta thing... I think 90% of this is all in the head, but its so hard to overcome! I realize that I get really scared in places that it has happened before, and am fine in places that it doesn't or hasn't happened. Example: It's never made any noise during Physics, and so for the first 10, 15 minutes of physics I freak out and am uncomfortable, but I remind myself its never happened before, and I'm fine. In Psych class, the room is a HUGE hall and so it would be harder to hear noises (plus the prof speaks through a mic/stereo system) and i've never had a problem with it then. But in Drama class, which is my smallest class, its the worst for being scared and anxious, and consequently I've skipped lots of classes to avoid it.
Really weird/frustrating, whatever it is!