Hi Paul,
My ROM was horrendous pre-op.... I could not put both legs together flat on the bed, I could not even put on a pair of socks pre-op. When I awoke from my surgery and looked down under the covers my legs were both flat on the bed and together. At 7 weeks I could put a pair of socks on, my range of motion is still not perfect but getting better all the time @ 5 months post-op. At 7 weeks I played my first round of golf but my ROM then was not near to what it is now.
With that said.
WARNING Do not judge yourself by anyone else, everyone heals at a different rate, everyone rehabs at a different rate. Just because your range of motion is not someone else's does not mean failure it just means that you are different, besides you did not start out the same as other people. Also, don't listen to snake oil "patient advocates" who will tell you that Dr. X operated on athlete Y and that athlete ran a marathon @ 8 weeks.... that is not even close to the norm.
Relax for now, if at 8 weeks things are not better than what you are now, you might want to consider some PT... a lot of doctors don't want their patients doing much in the way of PT before 6 weeks anyhow.
Above all, listen to your doctor.
Chuck