Meanings of almost lightheaded in English

I felt almost lightheaded with well-being, despite the pain which tore at my entrails.

She had got up feeling desperately nervous and almost lightheaded.

She was almost lightheaded with relief and a kind of giddy euphoria coursed through her, like the warm afterglow of a fine wine.

To-night she wondered with a kind of terror whether that terrible sleeplessness which had ended by making her feel almost lightheaded was coming back.

"It's probably a good thing." Aislinn pulled back further, feeling almost lightheaded.