According to our dentist, if you want healthy teeth the only two things you should ever drink that don't harm them are milk and water. Everything else is staining/corrosive etc.
This. Your enamel is still soft so you should wait 40 minutes to an hour after eating before brushing.
Top tip from the dentist - once you've brushed your teeth at night, and then rinsed, load your dry(ish) toothbrush with toothpaste once more and brush round to coat your teeth and leave on...