Based on instinct, she thought, "Neh, can't be possible. Impossible!" Reanalysing, her instinctive intuition convinced her, "Why not? At least it does seem very possible." Now she considers if she should take or have taken a step forward. She ponders over the probability of possibility versus impossibility, unable to go beyond 50-50 for either-or. If actions and speeches have implied meanings, she hopes for everything to be in 'expressed terms'. Implied is so 50-50, another probability of possibility vs impossibility.
A step forward cannot be withdrawn; A step hesitated may become regret.
She's stuck.