Thank you everybody for your kind and helpful replies! I guess the consensus really is not to panic, but do stretches as I feel capable, and for sleeping, at this point the main thing is to be comfortable enough to do so. My husband rushed out and bought a thick woollen mattress topper yesterday, and last night was easier than the night before so that's something (cash flow is an issue at the moment but later on we'll be able to buy a new mattress of the right sort)... Today I've decided to do 10 minute periods of lying flat at intervals, and I am doing some extension exercises as part of my physio anyway. Also when I see the physios next Tuesday I hope they will come up with some other suggestions (the surgeon has already suggested half hour periods of lying on my front, but I will only start that once I am confident I can move myself about that much as my husband has had to go back to work now!).
I suppose I worry about retaining the flexion contractures because a) I want everything to be perfect! and b) in my teens I first developed lower back problems and I now realise that was when the contractures were forming, and they caused my posture to change, hence causing muscle spasm in the lower back. I'd like to get back "normal" posture, but as Pat said, it's not going to happen overnight if I've been compensating for rotten hips for most of my life!
At least every new day I can see and feel a palpable difference in my mobility. It was really challenging having both hips done 1 week apart but my surgeon says that if it can be done that way, the rehab gets the most out of both new hips. He says that if you get one done and you still have a bad other hip, you can't get the most out of the new one due to the restrictions of the other one that hasn't been resurfaced yet. But it was still VERY scary going in the second time (I found out afterwards from his PA that a lot of people run (well, limp) for the hills and postpone the 2nd surgery!). It also sounds like from reading this site that my hips were a lot worse than a lot of US surgeons would tackle - I had bone cysts galore - but on the really bad side, Roger grafted some bone from the acetabulum to help with fixation of the head component.
By the way, I was surprised to see that my surgeon, Dr Roger Oakeshott (Sportsmed SA, South Australia) isn't on your list here - he practically pioneered the resurfacing procedure here in Australia and has a fantastic reputation. He also was part of the team that developed the computer software that apparently can get the implant alignment within half a degree of the original. I am certain he has done more than a few hundred resurfacings, and he has an excellent reputation here in Australia. So I think it would be worth checking him out!
Thanks for the helpful hints,
Catherine