I am not going to provide that good of a service for the medical staff since they abused me.
What was it that they ended up doing to you?
I had to clean up their office area, but I was too slow for them, so they didn't allow me to sit down for over 30 minutes.
It's not right to do badly at your job just to get back at someone. You should talk to them and open a line of communication so that problems can be resolved peacefully.
Yay, I love people telling me what to do.
It makes sense that you are upset with the staff for treating you in this way. It is never a good feeling when you feel like you are not being treated fairly.