When I run hard, I often get burning sensation in tummy and chest, excess salivation, aching jaw, ears and feel generally unwell. If it is acid reflux, what should I do, as it doesn t happen all the time. Its just when it does its horrible. I had suffered with bulimia for 10+ years. Would this heighten the chances of getting heart burn etc? I am 35, female, light smoker, quite fit. Thanks