Is 21 months to young for a toddler bed?

Cloe has always gone to bed with no problem. We can lay her down and with minimal fussing she just lays there and goes to sleep. Well something has changed .... the last two nights when i put her to bed, she just screams and she has figured out how to climb out of her crib. I am afraid she is going to get hurt but i think she's too young for a toddler bed. I don't remember when I transitioned Elijah into a toddler bed - he didn't sleep in it anyway. He hated his room being upstairs by himself .... but that's a totally different story! BTW, he's 13 today - can you believe it?? Any thoughts?