I'm sure a fair few of us have forgotten at some point to apply PH bond, I know I did when I first took on gelish, and like you worried like crazy!
But everything was fine.
As long as your prep was spot on and you did cleanse too I think you'll be okay, if your client does have a problem with peeling then you will know exactly what the problem may have been and you can offer to repair them for her.
It was a one off and I'm sure you won't do it again, I'd try to just move on from it now.
To settle your mind though you could perhaps text her in a couple of days to see how she is loving her new nails!
This may allow her to open up to you if anything has happened to them, I bet all if fine though and she tells you how much she loves them and how many compliments she has had!
X