baby weight

Cindy💕 • 18, mummy to George 31/07/16👶🏻💙 fiancée of a amazing man 5th Jan '16💕
So 5 weeks ago my son who was then 6 weeks old weighed 11 pound 3 and now he weighs 12 pound 5, yet before he was putting on half a pound a week but now it's slowed right down, is this normal?