Frankie suffers yet another break

I can barely type this; I take him into Petsmart in a buggy on his huge pillow with a leash on so he doesn't try to jump out, yet he did today and broke the tibia in his already mangled leg. I was standing by him and still couldn't reach him fast enough as he went over the opposite side of the buggy.
Kim from CAP immediately drove in from Sugarland on her day off to Fry Road and rushed him back to Dr Chalkley at Westbury.I just happened to have doggie pain meds in my truck so that helped. Initials xrays aren't great, they will do some more diagnostic work on Friday and see if they can still try to save the leg.
Dr C was nice enough to worry about the extension of my time involved with doing the rehab, but I told him that was not a problem.
Except for horrendous pain at first, Frankie was wagging his tail and licking everyones hands at the clinic, what a great dog he is.
I feel so badly about this.