HELP (feeding)

So my baby is now 12 weeks and 2 Days. She’s had bad bad colic ever since the start she’s already teething and has to have lactose free milk. Which made her a little bit better but now she’s sucking up every single bottle doc said she has reflux so she’s on gaviscon which isn’t helping at all, she’s also screaming in between having her bottle like she really wants it but can’t like she’s in pain, she’s also got very very dry skin can anyone help?