Baby weight!

How much does your baby weight at 4 month check up? My LO is exclusively breastfeed baby he is 22Lbs 5oz . I was told is completely normal and pediatrician isn’t worried about his weight because he states is healthy weight I get so many cute comments that he’s so chunky and looks so cute, his rolls make him look cute,etc but damn my back is killing me!! I mean I love him so much but I can’t imagine how will I be able to carry him at 10-12 months? He loves to be carried. My daughter weighted that much at her 1year appt so I’m worried I won’t be able to carry him as much as I did with my daughter. I’m also having a very hard time finding clothes for him. I mean on sets I need to get a big size so the bottoms can fit even tho top fits large. Any advice on where I can shop for his clothes would be greatly appreciated. Also any tips on how you handle it with a big baby? TIA!!