Confidence boost from stimulants

I became "alpha" when I was on concerta for a brief period (30 day script, never renewed). I stared down others, when normally I'm too shy to make eye contact, I approached women out of the blue, something I never had the balls to do before.

I even had a blast clubbing, dancing and socializing the whole night. I mean, god, I'm a wallflower at places like that.

My counselor suggested that these effects reminded her of cocaine. It seems ritalin and cocaine are closely related substances.

Is this confidence boost a normal thing and how long does it last?