Hello, and I hope I can answer your question. The main organs of your body in the left cheat are your left lung, heart and stomach. Chest pain can occur from any of these organs. Obviously, the biggest concern when someone has cheat pain is that they may have a heart problem. But cardiac chest pain is usually associated with chest pressure, or nausea, or shortness of breath. Similarly, your lungs can hurt because of a blood clot or other dangerous process, but the pain would have other associated symptoms and not go away by itself. The greatest likelihood is that you are correct- you either pulled something, or you has a gas bubble in your stomach, which is pushed up higher in your chest than when you aren t pregnant. This can produce a sharp pain, and even hurt worse when you take a deep breath or move, but will pass quickly by itself and have no consequences. So if you have no more pain I do not think you need to be concerned but if it comes back and lasts more than a few minutes or is associated with any other symptoms like nausea, dizziness or shortness of breath, I suggest you go to the emergency room for evaluation to make sure your heart is OK. However your history sounds most like a gas pain and hopefully it will not recur. I hope i answered your question and good luck with your pregnancy. Sincerely, Dr. Brown