@agingdonna - "Anyway the question is…would it be nerve damage, or re-alignment of a leg that is not used to being straight, or could I be over doing it. "

It could be the realignment, but mine worked to my benefit. I had sciatica on my left side before I had my 2nd TKR. My toes turned in and I walked with a drop and rotation on my hip, I think it was a gait adjustment to keep pressure and pain off my knee. My knee was straightened with TKR, and I have not had problems with sciatica since. But it's conceivable that any change and realignment of the leg might irritate the sciatic nerve.