Fever, Chest pain. Or viral infection?

Hello, Doctor(s),   Since the past two months, I'm suffering from mild fever which touches maximum 99.5 F and comes back to normal in the night with sweating. Also, mild stomach pain in the left and middle abdominal (since past two months), excess burping and gassy before and after the meal, loss of appetite, chest pain in the left and right side with numbness on same side hand. Also, I feel muscle pain and tiredness the whole day. No weight loss, no cough, no vomiting, no running nose. Diarrhoea was in starting for one or two days (when it started two months back) with red blood within stool but now nothing observed. Not able to empty the stomach completely. Recently, I have done with my testing of ECG which is normal. Kindly advise me what kind of problem it is? Is there any medicine could be taken for these symptoms. Is it related to any bacterial or viral infection? Please assist and provide me with your guidance to overcome this problem.