Legal Question in Employment Law in Maryland

Re: Can my boss ask me to undergo psychological treatment?

Based on the facts that you present, the answer is no. This would be

an action that is far outside of having taken off one day. The question is why did you leave?

Your pay can be docked accordingly. Also be advised that Maryland is an "employment at will" state which means

that other than discriminatory or retailiatory firing, you can be let go with little explanation.

This boss appears to be somewhat oppressive. I think I would be looking for a new job.