Puzzling behavioral problems for 1year old Sharpei/Lab mix

[denise56921]

Just recently my one year old Sharpei/Lab Male, has started showing fear of our kitchen. Which is where he normaly sleeps and eats at night. When we make him come in, he starts slamming his body into the backdoor(he is 90+ lbs.) When it doesnt open he runs to his bed and refuses to budge. We even tried waiting him out. He sat on his bed for almost 2 days-before he was crying so much(probably had to go to the bathroom)me and my husband had to carry him out. Nothing that I know of has happened to him, that would cause fear of the kitchen. But aside from that he rarely comes out from under the porch-which we have lots of land so thats unusual. And his"spirit" seems to have disappeared. Still eating and drinking like normal-as long as it's not in the kitchen. No other illnesses. He had been hit by a car at 8 months-but suffered no major injuries. We have another dog who has no issues. Any advice would be great.