Well if you didn't eat any dinner, it is definitely A O.K. to eat one brownie, I bet you ate less calories that way ;)
I'm so done with this week too and don't feel bad, I've messed up a couple times this week too but I'm not going to beat myself up over it.
Yum. Sometimes a brownie is the only thing that will make it all better. :-) Therefore, your overall health would have suffered if you HADN'T eaten the brownie. :-)
It's JUST a brownie. You are doing a great job!
youll be FINE!!! if I were going to fall off the wagon, though, I would definitely do it with one of these!!