Is the hesitation and confusion after repeatedly performing Salatul-Istikhara regarding the decision to retire considered a result of Istikhara?

Hesitation in retiring after performing Istikhara and resolving to do so might be a diversion from Allah. You should do what your heart feels at ease with after Istikhara, whether it's retiring or not, and abandon what you feel aversion towards. For indeed, goodness lies in what you have done, Allah willing, as long as you have sought guidance from Allah.