Does anyone else get this and/or have any strategies to combat it:

I can be just bumbling about doing stuff and all of a sudden i catch myself thinking "wow i've been feeling good for a while now, i hadn't realised i hadn't been feeling feint/heart fluttery/anxious" usuallly within a minute of this i get the first tightening of the throat and it can just go down hill from here. I often think at the time (which i am begining to realise is SO not helpful) 'maybe my body new that somthing was up and that's why i realised i had been ok and that i was just getting the early warning signs of something bad'.
is it really likely that i was actually fine all along and that thinking about how good/normal i was feeling made me think about how i feel when i go down and therefore actually feel that way? if so, why do i do it to my self, as it is reallly no fun WHATSOEVER [:(
anyway, just wondered if anyone else experienced this or could offer words of wisdom
ttfn
phil