I've felt fine all day up until about 7 hours ago. I noticed a rotten taste in my mouth so I brushed my teeth and chewed on mints but it didn't go away. The taste comes whenever I burp and nothing I've eaten or drank has made it any better. It also makes me slightly nauseous. Also, my stomach is constantly gurgling, sending me to the bathroom (diarrhea) every 5 minutes. I do not have a fever or the chills and my body is not aching (apart from my stomach). I ate cereal this morning, nacho and beef taco's for lunch, and a subway sandwich for dinner. Yesterday, I'm afraid that the meat that I made a sandwich with may have been old (sell by: mar 17). I've been drinking water since I felt ill. What could I have? What should I do to get rid of/help it?