Hello

I am a first time snake owner. My roomate and I rescued our snake Rusty from a friend who's housemate was not taking care of it. He adjusted very well and normally we feed him about 10 feeder fish every 4 weeks. A few days ago, we put in about 10 feeder fish and he still hasn't eaten them. He also looks very disoriented and it seems hard for him to move without shaking his head. My roomate sez he may have been frightened by our cats however he's been fine with them for the past 6 months. Could he possibly be sick?? I'm very worried and would not like to touch him, as I don't want to worsen any possible condition. Is this normal for a snake? Also we live in NYC and it's pretty cold over here (25 degrees F). We have put the heating lamp on at 15 minute intervals. Thanks for your responses in advance!