It seems to me that when we are dealing with anxiety, that we become hyper aware of every feeling of being 'off' and it becomes a red flag...which then brings on all the more symptoms...
Do you remember, pre-anxiety, ever feeling tired or maybe a little weird, and briefly noting it...and then dismissing it? So it passed after awhile, and you never gave it another thought.
We are organic creatures, and as such are imperfect, and prone to not always feeling 'perfect'.
The problems then arise when we experience one of these episodes, and filter it through our anxiety...which leads us to negative/fearful thoughts and worries.
'I don't feel well...there must be something wrong.' for example.
Trying to simply observe our symptoms, accept them, and know that they will pass then becomes very important!
I hope that you feel better very soon.:)
S.C.