"...they even used a shaver on me"
This actually isn't a good thing... and illegal in many states! The shaver is a razor blade and can take off a toe in one swipe. Rarely disinfected properly, they actually take TOO much skin/callous off, which you need for protection from walking, high heels, runners, dancers, etc. Also taking too much off will make it grow back thicker and faster.
Please refuse the razor next time!
-From a nail technician with 14 years experience