tree - sounds like endoftermitis, on top of everything else.
It's really hard going at the moment, all the Christmas stuff, play stuff, etc. etc. They've been going since the beginning of December with only a week off and they're all knackered. Believe me, I know, I'm the same and I'm 35 not 4......
How old is treejunior? If she's not five she doesn't HAVE to be there yet, so you could have a couple of days off to do some Mummy / Daughter stuff (is there anyone who could look after demandingbaby for an afternoon to give you some time together?)
Maybe see if you could pick her up at lunchtime?
Does she go to bed early? Maybe an extra hour's sleep would help.
On that note, I'm off to bed myself.
Hang in there, only another week-and-a-bit to go.