Thanks for all of your replies I will mention it to my OB but I don't see him for another 2 weeks so it's nice to know that it's common (not so great about being up half the night peeing though )

Taryn, I know what you mean...icy cold drinks are what I'm desperate for!

Thanks daytona's mummy - I've got some quickeze so I might give them a go, also looking forward to seeing whether we get some good pics at our 18 week scan, non of DS's scans were very clear so this could be the upside to spending half my life in the loo!

Thanks again everyone for taking the time to reply