Very basically the dispute is over car parking at work. Been going on for a few months now and had problems with the guy before that. Today I finally snapped at the guy and told him to explain why he kept picking on me.
No suitable answers were forthcoming so I gave him my name badge/tie/apron (yes till staff wear aprons

) and tell him I'll be back to deal with this.
Go into Personnel (yes Morrisons are archaic) to attempt to file a greivance with him but he butts in and has me suspended at full pay
Yeah I've done wrong but the reaction has been totally over the top and I intend to fight it all the way where possible
I will have my Line Manager sitting in on the meeting with me on Monday but I don't know who will be running the show yet. I plan to take a dictaphone with me as well so that I can record everything that is said.
I haven't joined the union and kinda wishing I had now but not sure exactly what to do in this case.
//edit:
In my eyes this is petty btw as I (a cashier) have been picked on (imo) by the manager since he arrived 6 months ago. I have not physically assualted him or verbally abused him to my knowledge so I doubt it will go that far.