it is unlikely you have caused harm, but i would recommend you get some help re the reflux and if you are going to wean duue to reflux it should be inder the guidance of a HCP
her weight is irrelevant to this
nhs advises no solids before 17 weeks, but to aim for 26 weeks, when the babys gut should be mature enough to digest something other than milk
it does strike me that 4 bottles a day is not a lot of milk for your baby , at only 18 weeks.
if she is being sick and not getting much milk, her weight gain might be slow, and giving food acutally wont really help that
if you are feeling sick with worry, i would stop weaning unless it is under supervision and look at getting medication for the reflux if appopriate and getting more milk into her
it is not about whether the baby like sit or ' it never did me nay harm' but whether the baby is pysically mature enough to digest something other than milk, and at 17 weeks, babies tend not to be ready.
signs of readines sare sitting unaided, good head control, loss of tongue thrust reflex, and being able to pick up, chew and swallow a piece of food. waking in the night and wanting more milk are not signs