It certainly sounds like a panic attack and if the Xanax worked that probably tells you that it was. Yes many people have abdominal pain with their attacks plus just about any other symptoms you can list.
However, if you continue to have severe pains that return or change, you should always consider calling your physician.
I am sorry this class is so uncomfortable for you. We are here to support you.
Moderator Anxiety ~ Panic Disorders
*~* Not a mental health professional at all *~*
Dx: Anxiety/Panic, Depression
"If you doubt you can accomplish something, then you can’t accomplish it. You have to have confidence in your ability, and then be tough enough to follow through.”