my boa's acting funny, opinions please...

[dvs]

Ok, I've had this boa for a little while now... it's a male and I'm assuming he's about 2 1/2 years old and measure's about 6 1/2feet.

Lately he's been acting very strange..... he does this thing with his head that is really weird. He kinda curls his head back and sways his neck and head back and forth in a very sloppy manner. He usually only does it when I first pick him up and then again when I place him back in his enclosure.... neither one of my other boas has ever done this and I've never seen any other boas display this kind of behaivior.

I know it's hard to tell without actually seeing the behaivior for your self but does anyone know what might be causing him to do this? any opinions would be much appreciated.... I'm really lost and kinda worried something may be wrong with him, thanks in advance.