Is it normal for a toddler not wanting to drink milk?

my son is 19 months (3 months prem) he has never held his own bottle he just refuses to which i don't really mind because its the only time he snuggles up with me and i give him his bottle. he was down to two a day, one in the morning and one before bed. but now he wont take any milk for me at all. i have been trying almost everyday to get him to drink milk from his cup instead of a bottle but he won't do that either. i don't want him going off milk hes far to young! i have been giving him extra dairy products to try and compensate and i have been using almost a full bottle to make up his breakfast. he won't drink water for me either so i have to put a drop of juice into it but at least he will drink that from a cup. im brushing his teeth(the only two he has) almost 4 times a day because i don't want them to get cavities from the juice. is this normal and just a phase?? maybe hes teething?? any advice please??:)