Oral-BKid's Battery Toothbrush Featuring Marvel's Spiderman, Soft Bristles, for Kids 3+

Does the timer just go for 2 minutes? Or does it do the 30 second reminders too?

Are the regular oral b replacement heads compatible with this kids brush? Are they the same sie?

My dentist told me to switch to a child's toothbrush because my mouth is small. But reviews say this head is no smaller than the adult toothbrush??

How to change brush? Why so hard