Discipline means "to teach". No, it's not too young to discipline a toddler.
When a child is very young (like yours) s/he needs to redirected...even at 14 months.
Use a firm voice when needed.
Ex. When my toddler screamed in public at the playground as I was lifting her from the swing...I said, "It's time to go home. We need to get our lunch. She screamed louder. I picked her up and carried her to the car. I put her in the car seat and said, "It was fun swinging on the swing. Now, let's sing our ABC's as we drive home." I sang in a silly voice...and off we went.
That's discipline/teaching. Action and learning limits... She would've stayed on the swing for another hour!
When I was training to teach parenting workshops, one of the PhD's I was trained by said this to me, "If you don't take care of simple discipline issues during the toddler and preschool yrs, then, the teen years will be that much, much, much more difficult."