Baby underweight?

[elodieari]

Went for our 8 week check today.
He was born 8 pounds 12, and at 8 weeks he is 11 pounds 3.

Is this something I should worry about?
Doctor said he's in lower percentile for growth.
He's formula fed - why is he not putting in enough weight? We feed on demand. He does have tongue tie which I'm waiting to get done. Could this be stopping him feeding enough?
What weight should he be at this age?
Worried

How many times has he been weighed?
The important factor is the pattern ie is he dropping down the centiles?
If he has, and without a chart one can't know , could one of the weights be wrong. It does sometimes happen that one set of scales was in accurate so if you have only had him weighed twice , say, you may not have enough information to know what the pattern is. You need a good set of weights. Is your baby thriving otherwise ie smiling, happy feeding well, sleeping , playing, dirty and wet nappies? These are all good signs. What has your Dr decided to do? If worried they will refer you. If just concerned they will continue to monitor eg weekly weights and review.
I assume the GP found no cause in examination.

No there isn't a correct weight as such as some DC are destined to be big and some are small. The important issue is whether your baby is growing at the right weight. What does your HV think?