Potty Training Fun!

First just a funny picture! I found Wes in the bathroom doing this:and singing "Stinky feet, Stinky feet!!"

Anyway, so we bought Wes new "big boy" pants, AKA underwear. And he is thrilled. We made a special trip to the store, and talked about how he can use the potty now, and keep his pants dry, and no more diapers, ect, ect, ect....
So we put them on him, and I'm of course paranoid that I'm going to be swimming in pee by bedtime, but it's not bad, for the first hour and a half. But as soon as I let my guard down, my living room rug gets a soaking. Not too big of a deal, especially when you get the "what the heck happened mom?" look from Wes. (I think he didn't get the idea until right then.)
Two hours later, it was not pee that I was cleaning up, but luckily it was only from the underwear and not from carpet or walls or beds or couches or the many many many different things it could have been. The rest of the night went somewhat smoothly other then drying off the wall behind the toilet because he doesn't understand the concept of aiming too well yet, but he was trying, and we didn't need a new pair of underpants.
Then this morning, he jumps out of bed, and wants to use the potty. No problems at all. The aiming was perfect, my floors and walls were dry. Great.
However it is then time to leave and as we are headed out the door, as an afterthought, I figured I should ask if anyone needs to use the potty before we leave. "I do" Wes yells proudly. We run to the bathroom, put him up on his new seat, and he's so excited that he's going, he throws his hands in the air yelling "I did it." At this point I feel the warmth on my leg, and realize he is now pointing directly at me and my pants, and with my really quick thinking abilities, I reach over with my 'water tight' hands and try to stop it, now making it stream down my arms, and directly onto his once dry pants and underwear. (Guess my hands aren't as water tight as I thought.)
So after a change for both me and him, we made it out the door, and on our way to Lori's house. He starts complaining almost immediately that he hurts. (This isn't really new, since he hates his car seat and is always saying that it is too tight.) So I ignored it at first. However, about halfway to Lori's he is crying and whining and really upset. I ask what hurts and he says it's his bum. After a little more crying I figure it's best to just pull over and find out what the problem is. So I get out and get him out of his seat, and ask what's wrong? Where does it hurt? He reaches back, pulls at his underwear, smiles up at me, and says, "It's just a wedgie."