I’ve suspected a small stroke for a while. The sudden need for thick glasses...and the puffiness and weight gain could be from strong medication.
If she does have another episode, and it occurs in a private setting, we'll never hear about it. If, however, something happens in public - such as during a speech with the TV cameras rolling as paramedics come to the stage to attend to her, it cannot be explained away as "fatigue" or some other nonsense. Her candidacy will be doomed at that point.