Waiting on a tech?

[StlCards]

I had a situation like this last night, but with an intentional foul.

A1 had had the ball stolen by B1 at A's end of the floor. A1 and B1 both go to the floor but B has a breakaway. A1 is mad because she fell and lost the ball and throws an elbow into B1 while on the ground. I waited to call the foul after B scored the layup but wasn't sure if this is right. The more my partners and I thought about it, it should have been called right away since that reduces the risk of retaliation. Thoughts?