Anyone got bad diarrhea, nausea, and cramps near the end of the pregnancy?

I'm 36wks and I've had the worse diarrhea of my life for 4days now.

The back pain, cramps, and pressure are killing me.....

I was in the hospital last night, they monitored my contractions for 6hours (I started contracting so I felt I had to get checked) the contractions got weaker so they sent me home. Never checked why the heck I have this diarrhea from hell, nor did they check if I'm dehydrated...... I left a message for my doctor this morning, but still no freaking call back.... I'm getting very exhausted and aggravated. I'm starting to think they're not taking me seriously