Seconded. I had this too, and I found the best way to keep an even keel at the table is to play a lot of hands, so your mind recognizes that it's just another hand (one where you happen to be way ahead, of course, but still). Granted, that's not much help to you now, but over time it'll even out.

If you have some spare time, and don't do this already, try playing some online poker, if even for play money -- you see a lot of hands fast, and you can get your celebration done where no one can see or hear you.