I know I'm not the only one to be suffering from this so wanted to pass on a tip I got from my GP. She advised to take a magnesium supplement before bed (apparently safe to take up to 350mcg per day) so I took one last night before I went to bed & have had the best night's sleep in a long time.
Please check with your own GPs/ midwives before doing the same, just passing on something that worked for me & know it might not be for everyone.