There are different reasons on why you feel pain on the left side of your body. It is best to go to a professional because you may be having trouble with any of the following organs: Kidneys, Ureter, Fallopian Tubes, Ovaries, Testes, Lungs, and Adrenal Glands. If you are having a hard time breathing, then it may be your lungs. If you are having trouble peeing then it means that you have a problem with your ureter. There are a lot of problems that may be happening and it is BEST to consult a doctor for that.