Gracie *hates* the half bath! Occasionally I put her in there if we are going to be gone more than a couple of hours so that she has room to move and go potty (on peed pads) etc. She cries when I shut the door, and when I get home and open it, she screams and runs around frantically! Even when I pick her up she tries to wiggle out of my arms.
She sleeps in a small kennel, it's plenty big enough for her to move around in but small enough that she feels secure. We put her beside our bed the first night and she whimpered at first when we turned the lights out, but I would just tap on the top of the kennel and say "Quiet" and eventually she figured it out. She cried maybe 5 minutes the first night, 2 or 3 the second, and never made another sound from that time on.
I think your little one is definitely showing separation anxiety. I'd try something small beside your bed so he knows you are there within touching distance and that he's safe and secure. Put him in it several times during the day and DON'T let him out if he's crying. Tell him to be quiet and then when he is, he can come out.
It's hard training him, and even harder if he trains you!
