Dementia of pain/beam end that sagged

Hi

A woman was in the church tower. The loft was burning.

Miss Mayfield was fighting against the wave of

dizziness, the near dementia of pain, and smoke and noise,

and the necessity to choose beween two evils. She looked

up and saw that near the head of the stairs there was a

licking flame, a beam end that sagged.

Does it mean that she fought against the dementia caused by pain?

I just take it to mean that there was a beam and its end started to sag?