i have no ideas about your strange sensation, kittn, but can i go OT for a sec? dd2 just came downstairs from her nap, walked over to the computer & said, "those are marbles." it freaked me out for a minute because i thought, "can she read?" i finally realized she was referring to your boys in your siggy.
seriously, i cannot for the life of me figure out what your sensation could be. air, maybe?