I put Mya in a toddler bed at 16-17months. She was ready tho. I never had any problems with her at all. Also i wanted her to be used to her bed by the time this bubby was born. She sleeps in a cot at her nan & pops house & it doesn't seem to confuse her. Although she doesn't spend alot of time there atm.
I would be furious at ur day care provider & would definatly be talking to them