Too pull manager up about bitching?

[Icloud154]

Apparently I'm no good at my job. Shall I pull him up on it?

Not just that, a couple of other things have been said and got back to me. Shall I pull him up on it and question it?

What's the context? How do you know about it?

Are you a member of a union?

Behind your back? Hell, yeah, I'd be talking to him about that and asking for proof, logs, the lot. Just be careful he doesn't promptly bring all that up and starts proceedings!

A colleague gave me the heads up to what he thought. The colleague is very quiet usually and wouldn't say otherwise and we get on quite well so I know it's reliable. Apparently I think I'm too good for the job and my head/hearts not in it.
I love my job and this is really a shock to the system.
I don't know what to do!

And no I'm not part of a union :/