Nice times on D2!
7:21 is a solid D3 starting time. My first D3's at a level have tended to be real slow as I get a feel for it. But, even my second D3's have been L4 - 7:53, L5-9:37, L6-10:29.
Be careful about the arm. Better to slow down and let it recover than get sidelined by an injury.