So my dog demonstrated some behaviour last night which I've never witnessed before. At the end of a long hot day when we were settling into our camping trailer, we brought our dog inside for bed, but when I put his food bowl down in our room, he was kinda whimpering, took only one kibble off the top, dropped it on the carpet, then started using his nose to try and "bury" the kibble. I put it back in his bowl, but he merely grabbed another one, and tried doing the same thing, brushing the carpet in the direction of the one kibble with his nose. I eventually moved the bowl and put it on a little rug, but he came out from under the bed, whimpered again (the same sound he usually makes when he's sore on his foot), walked over to his bowl and tried to flip the rug over his bowl with his nose while making the whimpering sound. Finally I took the bowl out of the room, and that seemed to make him happy, and he went to bed. He acted completely normal all day, played in the water, ran through the woods, and he's been normal again today.
I get that he was probably trying to tell me that he didn't want his food, but why the weird behaviour instead of simply not eating it?
He's a 4 year old German Shepherd/Black Lab cross.