If I were you I wouldve asked this question at least a few days prior to this little meeting, but i understand that you may not have known about it... My suggestion is this-
I noticed that when I jelqed really hard at very low, almost completely flaccid, levels I got raging hardons. I had only done them for a few days and got this result, but I dont really know if its going to work for you in the span of just a few hours..
or
You could also take the easy route and just dip your finger in hot sauce and shove it up your ass.. i heard that works :s
Youll do fine buddy im sure.. pound that bitch out!