Gosh i am sorry to hear of your suffering this does sound like an emergency to me.
I am wondering if there is an obstruction going on with you? But dont quote me as i am not a dr just with your bad breath and loud bowel sounds... etc. Symptoms include pain, bloating and vomiting, constipation/diarrhea. tummy will also be tender to touch.
If so, you really do need someone to look at you asap!! How can you get their attentinon? Go to A and E or ER - ASK for them to give you xray and CT scan.
I dont know much about fistulas but know they are very painful and always need surgery.
i do hope it is not the above but please keep us posted.