I just picked up a 120 sr this past weekend and hoping to get some advice from those of you that have flown one before.This is my first non coaxial heli so i did expect a little bit of a learning curve but this thing is kicking my butt. I do have a noticeable TBE at hover and shaking. I don't know if this is leading to my other issues or not. Is it normal for it to want to swing wide like a tail out skid and gain speed when turning with rudder at hover and slow ff? At hover i usually catch it but in ff it normally results and me getting several steps behind it and crashing or it swings tail first into the wall or shed if im outside.

The TBE is from a bent main shaft or bent feathering shaft,maybe even a bad tail rotor motor or bent shaft on it. etc. likely.
You're experiencing, other than those symptoms, normal stuff.
I'd get the shaking/TBE taken care of then do this :
Don't worry about doing any forward flight until you can hover out a whole battery pack keeping the heli right in front of you with no more than a couple feet difference.
Then start working on forward flight basics, nose-in,etc. Doug