ok so I have 2 DC's , DD is 3.9 and DS is 9 months.
9 nights out of 10 its me doing bedtime on my own as DH is often at work / doing sport - which is fine with me :)
however... I am finding it harder and harder to cope at bedtime - the rest of the day I am fine, but I guess I am tired come the end of the day, stressed, and I know 4 nights a week I have to work from home once they are in bed. DD being a clever little madam picks up on all this and plays it to her advantage... she knows how to push my buttons and drives me up the wall IF she wants to 
IF she's being good it will be all sweetness and light putting her to bed, nice story etc, love you mummy night night etc etc, then as soon as I am out of the room she starts f**ing pissing about. Either running out of the room, throwing stuff in the lounge, playing, singing, bloody anything to stay awake! This doesn't matter how tired she is - it just seems to be to wind me up! 
I am ashamed to admit I have resorted to smacking (something I don't believe in) simply because I am at a loss of what to do! I normally ignore the first few mins thinking she must be winding down, then go in and give a warning, when I next go in I take her teddy away, then after that is starting to regularly come a smack...
I don't even know why I am doing it because it does Jack all! She tends to carry on just to make a point for a bit then goes off to sleep!
Someone please help give me some coping strategies, we took her stair gate off as she discovered she could climb over it, or open it within a week - argh! I guess we were just lucky that she had never tried before!
She shares with her brother which isn't too much of a problem but we are in a maisonette so its EASY for her to know she has got my attention