Immersion

I set off walking to work today, and suddenly had a very weird sensation where I truly felt I should be gliding. It was pretty much akin to deja-vu, in that I came round quickly and realised that in this world I actually walk. But in the other world I glide around on rollerboots. Having spent pretty much the entire w/e existing in SL, my first self is experiencing momentary lapses into second self (as also evidenced by turning round to MT in RL and calling her by her avatar's name).
But i'm not overly worried. In seems like only yesterday that after a particularly heavy Quake session I would get into bed and close my eyes and wouldn't be able to sleep due to fighting my reflexive instincts, which were urging me to shoot-up a myriad of enemies. Obviously they weren't really there, but the after-effects of immersion can stay with us for days...
I haven't played Quake since 1997. Not only have I not played it, I haven't even thought about it. So I'm not overly concerned about SL/RL lapses - perhaps I'm secretly hoping that it's just a phase...