knibbs, this might sound totally ridiculous but comes from personal experience.
Is there a smell from your washing machine? A bacterial gunge builds up in some machines. Changing detergent and an occasional hot wash can solve the problem. I find good old fashioned Surf and Lidl own brand powder good, tabs and liquid detergents bad.
Also look at your diet, reducing fat and processed and spiced food has worked for me.
To anyone that doesn't like me here.
I hope you need to pee 3 times tonight, but that you only wake up twice.