RNRGirl is right- some water is OK. It's your layer of insulation. You'll definitely get more comfortable at it the more you wear it. Just don't forget to body glide your neck. I've chafed there a million times from my wetsuit (where it velcros). Yeeeouch!
And I HAD to pee in my wetsuit during my IM. I mean- where else was I going to go when I was into my second loop with almost a mile left to swim? Plus, the water was cold (I had on a sleeveless), and I was starting to get REALLY chilly. It warmed me up and made me not have to do the "I gotta go" dance. When I got home 17 hours later, I washed it out really well and it hasn't smelled yet (and that was 2 years ago). Sometimes nature calls in the most inconvenient places...