Started HRT in March (ugestron and Sandrena gel) and saw improvements quickly, within 2 weeks hot flushes vanished (hurrah) had mirena put in in July as gp said it would be easier for me (I have adhd and was on the non-daily progesterone as still had a random period every 9 months or so) I said I was concerned about mirena as had it once before and it gave me permanent pmt (nearly divorced) but gp reassured me it would be easy to balance hormones by adjusting the oestrogen gel so cracked on. Have definitely been more irritated since and was building up to private blood tests to try and improve things (haven't got round to it yet). Now in the last 3 weeks have had the odd hot flush started off just being my face but they are becoming more frequent 4-6 times a day/night and more like the all-over hot feeling I used to get (although still not quite as bad as they were) and starting to disturb my sleep again 
Just wondered if this is common and if anyone else has had it what improved it please?