Dear LED,
I feel bad that your first teacher was so remiss on the concept. Sounds like you are on the issue now though.
With Reiki/ energetic work one can expect a bit of neg. energetic over slop for the channeler. But one should not be conducting or absorbing the recipients Energy with Reiki. At that point there could be profound Energy things happening for sure but it's not mindful Reiki.
Mindfulnes.
Intention.
Namaste,
Michael