my male veiled cham is about 4 months old now i've had him for about 2 1/2 months and recently has started acting real weird. some times he hisses and then runs away or looks like he is going to bite me. it's weird because he hasn't done this since i got him. and has been taking food out of my hand since the start and still does. also, I've handled him before but i put him back in the cage after a few minutes because i can tell he really wants to. what could be causing him to suddenly see me as a threat? i feel as if i can't get near him anymore. any input is greatly appreciated.