Hi, I had gone through your question and understand your concerns.
Hyperbilirubinemia is a very much common in all the children.
It is due to prematurity of the
liver.It is even common in baby with regular dates born.Check for RH INCOMPATIBILITY and ABO INCOMPATIBILITY.
The pattern of onset ,day , severity,blood bilirubin levels are important.
Your baby is absolutely fine.
There is no need to get tense.
If you have any symptoms like
vomiting ,dark coloured urine and stools,
abdominal bloating, then you should consult physician.
Continue exposing the baby natural sun daily in the ear;y mornings.
Repeat the test after 1 month(if recommended).
About weight growth it is absolutely fine.
Initially in the first week there will be fluid
dehydration and
weight loss common.Now the baby is having good weight.
Hope this answers your question. If you have additional questions or follow up questions then please do not hesitate in writing to us. I will be happy to answer your questions.