Well, I spoke to my GP and he was very dismissive. Apparently "some HRT makes you have a bleed and some doesn't. It's just the way they work."
I got the distinct feeling that he didn't have a clue. Either that or he thought he obviously knew better than me.
So I shall take the Premique for three months, see how I get on with it and then go back. I may go back to see another GP in the practice, although he's the one that originally put me on Clonidine!
So I'm not very optimistic!
Thank you everyone for your help and concern xx
ETA: after being made to feel like I didn't know what I was talking about, I didn't feel up to discussing Femoston. I'll leave that for another day if the Premique does not agree with me.