Sounds like you basically became an hourly employee.
Arrangements similar to what you have described are done all the time around here when plumbing or HVAC companies want to start an in-house electrical division.
I'm sure the laws are probably different where you are, but even so, you should definitely have a written contract outlining everything.
Since you are still placing quite a bit of potential liability on your shoulders by risking your license as well as your future income if something should go wrong, maybe even years down the road, the current business arrangement should be made worthwhile for both of you.
