I don't have much advice. All I can think of is for you to speak to a therapist. This person can help you with some coping mechanisms. If you don't have the money to see a therapist you may be able to get free sessions through your school. I'd see a medical doctor too - primary care physician type for a checkup- let them know your feelings and anxieties (plus physical symptoms)- don't be embarrassed- you can't get help if you don't talk about it- they can refer you to others for help. I know there are medications for IBS, but I don't know if they help for stress induced incidents persay. I'm not really familiar.
Also, a clergy person or church/temple/worship place leader may be able to help guide you.
