 [ Symptoms ] i have very loose diarrea upset stomach & bad lower back pain when i take a deep breath any idea what could cause it [ Disease ] i am sorry you are going through this it sounds very uncomfortable and pleasant there are many things that could cause the symptoms you describe i suggest you get a thermometer and take your temperature if you are running a fever in an adult that is over 101 degrees fahrenheit you should seek medical attention if you are not feverish it is probably safe to take a wait and see attitude be sure to drink plenty of fluids because diarrhea can cause dehydration quickly if drinking fluids makes your upset stomach worse then try sipping but do not avoid fluids altogether if you develop additional symptoms such as vomiting or if your symptoms get worse instead of better over the next day or two then you should see a doctor for an evaluation feel better soon