That is heavy for a 6 weeks old, but she was a big baby at birth so I would say she is fine, all babies grow and gain weight differently, as long as she is feeding well and is content then I wouldnt worry. Believe me hun you will hear a lot of 'do this' 'dont do that' 'thats not right' it comes with the job, I am 31 years old with 2 kids and I still have people try to tell me whats right and whats not !!!! Enjoy your baby hun xx