Moody teenage rabbit!

My partner checked on Ralphy this morning and came into the bedroom and said that he thought he looked a bit "off" and he wasn't eating. Alarm bells immediately went off in my head so I got up and went to take a look. By the time I'd got there he'd eaten everything my partner had put out for him and my partner came behind me to take a look. He was no longer hunched, but laid out and ignoring us. When I stroked him he was fine but he seemed annoyed that we had woken him up! (It was just the expression on his face.) Then he went to his litterbox behind the partition and like concerned parents we opened it up just to see whether there were any runny poos or anything to worry about and he looked absolutely outraged! He then sprayed the door (I think it was meant to go on me!) I know I'm anthropmorphizing slightly, but is this the teenage rabbit behaviour everyone's been telling me about?!

It could be. How old is your rabbit? Is it male/ female? spayed/ neutered?

Not eating or (in your case) being reluctant to eat can indicate dental problems.
Get his teeth checked out by the vet (back teeth - they will need to use an OTHOSCOPE). Pickle did not completely stop eating when he needed a tooth removed, he was just reluctant to eat so I'd deffinitely get it checked out.
Plus, while they're doing the dental he can be neutered to stop him spaying