I have a history of gastritis r/t IBS s/s which I take amitryptaline for. I forgot to take the amitryptalline for a few days and it felt like the gastritis occurred. However, I have restarted the medicine. I understand that it will take a few days for the gastritis to calm down . However - The past two days, the pain has been located in the epigastric region below my sternum like it was before, but it is also on the left side of my chest. It worsens with deep breaths. It is much worse when laying in bed. I do not have a cough, have not had any recent injury, surgery, have not recently had a baby, have not recently traveled, etc - nothing out of the ordinary. My blood pressure was 128/83 which was normal for me. I do not have a fever. Could it be the gastritis or possibly something more? Costochondritis?