I'd say it is entirely down to when you feel is the right time to make the change
Jake went into a junior bed at 14 months with a stair gate on the door so he couldn't fall down the stairs (we had terribly steep stairs at the time and no way to put a gate at the top of them) but he had free reign of his room to play when he woke up.
Oz made the move from cot to bottom bunk at about 18 months - basically when he could climb out by himself!
At 19 months Edward co sleeps, but has a cotbed in the bed mode at the side of my bed. He gets into it now and then, and last night pulled the covers up and lay down - only to get out and into my bed to go to sleep
If you're happy with her being in the cot then don't worry about it Nic!