If you feel you have a complaint, go ahead and file. When you do, the company will have to produce documentation of prior action to correct your behavior or other attempts to get you to improve your performance.

Be careful with this now, and consider whether they will have documentation for all this (is it possible that informal chats have been had with you that you don't remember or that you might not have realized were attempts to correct your behavior). If you feel your performance over these last 6 months has been good and you can handle a bunch of stuff being brought up, then file.

Have you filed for unemployment and has it been approved?