I'm sorry you received a PM that was unapropiate. I PM people sometimes but mostly to give additional support, or to ask them for some extra support for a little more somebody in the furom.
Here is a suggestion to you:

1- You can in your profile indicate whether or not you want to accept PM's or not.
2- Forward the PM that was unapropriate to Dr. John or any of the monitors (who ever you feel comfortable with) so this can be addressed as well.

gab