Garganup,

I am sorry that you are going through this, but this is not the end of the world. Of course having that P will raise a red flag, but take the GMAT again and know that on the applications, there is an optional essay to explain just such a situation. I think that if you calmly explain that you did not know studying at the break was a problem, and do well on the test, then adcoms will understand that these things happen. I've helped clients who had worse situations, so relax, do well on the test, and you can explain what happened. It's not like you were caught cheating with another person during the exam.