Congratulations on your pregnancy. I don't have any personal experience, but I have watched my friends and family struggle. My twin sister only breastfed for a few weeks before she decided that it was better for the baby to go on formula and have a healthy mom. My best friend's youngest baby is teeny tiny, she was only 4 pounds at birth but other than GERD she is completely healthy. She's still tiny, wears 0-3 month clothes at 5 months and they are baggy on her I think you should just do what you need to do to stay healthy for your baby and forgive yourself if things don't turn out perfectly.