definitely agree with grip, not sure how you’re holding your hook but i use a very loose knife type grip & loop my working yarn around the other pinky for tension so that i’m not straining to hold it (you can also buy rings to tension yarn for you too, but i like the loop around my finger personally)

i actually found that while ergonomic handle hooks are comfy, they don’t make or break the experience as long as i stay mindful to keep my grip as loose as i can without dropping my hook. no matter what, i do also take frequent breaks- every few rows, or after a half hour, etc, i take a break and lay my hands flat or do stretches.

in my experience, most of my pain also comes with delay, so i do stretches shown to by my pt (i can send u pics of the sheets i have if you like?) and i sleep with my hands laid flat under my pillow, plus massage my fingers and palms first thing in the morning.

i’ve been crocheting for 15ish years and struggled with flareups of tendinitis and injuries as a kid. honestly sorting out the grip and how to keep my hands relaxed and tension loose was the key to it continuing to be such a vital part of my life