Weight “normal”?

Betsi

My baby weighed 6lbs 10 ounces at birth. At his one month appointment he was 8 pounds 8 ounces. He will be 2 months on the 30th. He currently is weighing 9lbs 6 ounces. I see all these babies weighing 11-12 pounds at 2 months. I can’t help but wonder if he is gaining enough weight? He is breastfed every 2-3 hours and given two bottles during the night of formula. Anyone in the same boat? Suggestions? Should I even worry?