I need help/suggestions please!

So I’m trying to wean my daughter from breastfeeding and I just started on Monday. I’ve been cutting out the sessions from morning until night. I just feed her during the night still for comfort and I really need it to because wow my boobs are full and kill from not giving them to her all day. Am I doing this right? It’s a big change for her because I use to nurse on demand and she’s so attached to my boobs. I’m pregnant with baby number 2 and the dr told me I need to stop because it could cause a miscarriage? So I’ve been stressing about that. 🙁 Any mamas out there that can help me get through this?? I would really appreciate it!! Also how long does it take for my daughter to be fully weaned and what do I do for my pain??? Thank you!