Possible health issue, possibly nothing? Please help.

[Huge Noob]

Hi there. I have a Brazilian Rainbow Boa, juvenile, male. He's about 2 ft long and as big around as my thumb.

Suddenly his behavior has changed. He seeks out one of the coldest spots in his enclosure, he curls up underneath the water bowl on the cold side of the tank.

When I pick him up, he feels cold. Also, his breathing seems labored / heavy. Like his body is very noticeably expanding / contracting with each breath. When I pick him up he seems fine otherwise, he displays a fairly normal amount of energy, and he doesn't have any weird behaviors going on.

Is this normal behavior for a BRB, or is something wrong?

Thanks!