tantrums when holding in wee?

[hairtwiddler]

DD is just potty trained and seems to have excellent bladder control - she can hold it in for hours! Twice this week I've picked her up from nursery and it's been at least four hours since she had a wee. Cue enormous (and quite out of character) tantrums. Usually settles once I've managed to coax her onto the potty or the loo.
Is this a common thing? It's driving me crazy! This morning we spent twenty minutes with her screaming for the potty, then changing her mind and screaming for her cereal, then asking for the other potty, which when fetched from upstairs just wouldn't do at all! I eventually had to give in to breakfast being served while on the potty.
Any tips for handling this?

My dd's have both done this but with poos not wee.
As you know the reason for the tantrums then you just need to keep calm (difficult I know)and encourage her to use the potty.

My two have both insisted on eating/drinking on the potty, watching a particular dvd, having a story read/song sung and my particular favourite was dd1 taking all her clothes off and taking her potty to the middle of the driveway to do her wee. So strange behaviour for us seems to be quite normal for them!

Thanks for response! She seems to be a bit bored of the potty, so the loo is becoming more appealing. Not sure what to do when she gets bored of that! Tantrums still happening, mostly when she's too busy playing to want to stop to wee!