Honestly I think a better sling might help. An 8 week old shouldn't be hurting it if it's fitted properly.
I've been 'baby' wearing for nearly 7 years continuously, with pre-existing back issues. What makes a difference between my back hurting and not is the fit for me. I'd rather carry my 4yo in a well fitting carrier (I actually do this every day as she has reduced mobility) then a 3 month old in one that's not right.
Otherwise, as much as you can, just enjoy the snuggly naps. They don't last forever. The era is being able to sit with a barrel of biscuits and watch tv whilst baby snoozes on you pass, or are limited to once a day (often with less opportunity to watch tv as they are more rousable). You won't get it with any subsequent children either, or at least not to the same extent.
Right now, your baby doesn't need weaning food preparing, or tidying from the mess they've made. If you don't have time to cook as you've got baby on you, and you eat a ready meal -who cares right now.
The good thing about having a baby that contact naps is the freedom it gives you. You can actually go anywhere (yay slings!) Or find a comfy sofa trying a friend house, or baby cinema, or the grass (in summer). You aren't stuci to the house.
I do get that it can feel claustrophobic when someone is always touching you though, so I'd try to make sure that the contact napping isn't always with you, so you can have more of a physical break sometimes.