@kimw - let me start off by telling you that this is in no way your fault!
I had an mua at 3mo. I was stopped at 78 and it would not gain anymore rom at all. The manipulation worked for me, but is still slow going. At 6mo tkr and 3 mo mua, I think I'm about 110.
When my os and pt started talking about mua, the first thing they said was that this was definitely not my fault. And that they knew how hard I had worked, it just happens in some people. Apparently, I grow scar tissue excessively, at least in that knee.
Of course my os did start talking mua sooner than 3mo but I told him I wanted to wait and see and he was ok with that.
Honestly, I would question why your dr is pushing you to have another mua so soon after the 1st one. And why he is saying this is your fault, because it's NOT your fault.
I would think though it's a good idea to wait and let it do some healing and get a 2nd opinion.
And you are probably doing way too much. At 3mo post mua, there is no way I could stand for an hr.
Your main goal right now needs to be icing, elevating and resting. You're having too much swelling to gain rom. For example, I just had my other knee done 2wks ago. First thing I did when I came home from hospital were those 3 things. Started pt on Monday and by continually icing and elevating, on Wednesday I had gained a whopping 10 degrees! That's a lot! And the more my swelling has gone down, the more rom I'm gaining.
So what I'm doing is icing, elevating, resting and taking my meds around the clock. You cannot do this too much! Just try it and see how it works.
I'm sorry this was a long post, I will be praying for you.