I don't work in childcare but I agree I think it takes a lot of energy and I know, personally, I would feel drained by the constant nappy changes, bottles, sleeps and trying to manage tanties.

I know you said you wanted to work with under-3s but have you thought about being a kindergarten teacher instead? I've been in sessions at my daughter's kinder and by that age, it's less about behaviour management and more about quality interaction with the children. Reading stories, doing craft etc. etc. - looks very rewarding particularly as you're the children's first teacher in effect and I think giving them a positive first experience with 'education' is absolutely priceless. I think with your Psychology background you may find that very rewarding too.

Don't get me wrong, I think childcare workers for the under-3s are vastly underpaid, vastly undervalued and they do an amazing job.