I was just going through this myself last year. I kept telling myself over and over that I would make it and I did! However it's wasn't pleasant, but that was b/c of one prof who went out of her way to make it hell. I'm sure your profs are much nicer, almost everyone is compared to her. Have you talked to your advisor and asked how long it would be? They limited mine to just 2 hours and it went by so fast. I made sure I was really prepared but at the end I wanted to tell them where to shove it. (I had to give mine in French too)
I'm sure you will do great but I also know that you will be sooooooo relieved when it's over. Throw yourself a big party!