My X4 Extender finally arrived and just started using it. Just have a few questions for those experienced with extender devices as i'm new to this. Did my first extender session yesterday. Only did 2 hours as I was more concerned about proper usage than actual time at this point. I had only planned to do 1 hour but the first hour went by so fast and easy that I decided to go two. About a hr 1/2 in I began to feel discomfort. I stuck it out for the 2 hrs but I would like to know if this is normal or if i'm doing something wrong? or maybe i'm just not used to the device yet? Any tips or advice that would be helpful to someone new to this?