Severe "gas" Or Constipation Pain In Upper Back Along With

Severe "gas" or constipation pain in upper back along with severe pain and spasms in bladder (sex in now painful too). followed by increase in pain and pure water diarrhea. Which is actually better than regular stool because a regular bm feels like glass shards are passing through my intestines (not anus). Also an increase to almost daily heartburn. All with crippling fatigue. Went to Er last week to be told that i have no infection in urinary tract and no elevated wbc. Put on meds to calm bladder spasms but other or "underlying" issue not addressed. No fevers. I have a gi intake appointment on weds., but have not been able to work or function. My quality of life has diminished so much that I feel depressed. Any ideas on how I can cope in the meantime?