A few points:
1. Try breathing deeply and slowly.
2. Try to stay in the situation without leaving to the bathroom next time; do whatever you were doing through the attack;
3. Figure out what happened before the attack, or what caused it, and how you can confront that issue in a mature way;
4. Remind yourself through out the attack that it's just anxiety trying to tell you something; thank your emotional circuitry for being ready and willing to work you up into such an excited state;

Hope this helps; I know panic feels terrible but you're going to be fine