Lots of posts have said some version of "The OP's first thought was to pull a gun." I don't read that. His first thought was to protect his daughter, and he thought of his gun as one of his available tools to do that. Isn't that why we buy and carry guns? He realized quickly that the only gun at his disposal was in an ankle holster, and that came into his decision making, but he used his wits to get out of a dangerous situation without drawing or firing. Who is to say that he would not have had the same result if he had a pistol IWB instead of on his ankle? He posted because he was shaken and wanted to remind those of us who read such things that we should never consider ourselves to safe too carry our sidearms. Completely valid point to make, and an excellent illustration.
OP, you did fine. You protected that which is most precious to you and you got home safe without needing a lawyer. There are people who go around looking for things to be insulted about; who has not had someone give you a dirty look or a hard word instead of thanks when you held a door open for them. The worst of them can be dangerous. You survived an encounter with one of those with no ill effects. Nice job.