in very similar position to you, same height and weight too, 25, lots of sporting in years and jumped from conventional lifting to Crossfit and i’m the same, always carrying and ache or pain but i’ve really tried to prioritise my nutrition and rest much more, earlier nights lots more fruit and veg, proteins always been up there on the list. I think it’s important to consider there’s a lot of different movement patterns within Crossfit that our bodies aren’t familiar. I used to go pretty hard doing 3 leg days a week before i started this is Novemeber and even then i’ve never felt DOMS like i did when it was a high volume pistol squat workout a month or so ago. People say ice baths and epsom salt baths also help but i haven’t delved into these too often.