To verify whether the wart has been removed, you could soak the treated area in lukewarm water for 5 minutes and rub the calls carefully with a file. If the skin does not show little black dots (little blood vessels, typical for a wart), the wart has been removed.
During the treatment, a layer of callus (hardened skin layer) will form. The callus is not a wart. The callus might need a couple of weeks to wear before the optimal result is seen. Renewed skin will appear smoother, slightly pink and regain its natural colour within subsequent weeks.