I have taken good care of my health for the last two years, with regular exercise, good diet, nice sleep, little stress and good habits. However, now with retrospect, I didn't do any strength training in my arms, leaving them quite weak and prone to injuries. After some heavy activities I ended up getting tendinitis in the elbows of both of my arms. Since then, I rushed to get myself the solutions that I could and got an ortholinear board with the lightest switches I could find, changed to the Colemak-dh layout and started designing my own split ergo mech keyboard. Now I have my keyboard, started physiotherapy and have been improving steadily.

At least in my case, I truly believe that if I had stopped before taking any of those actions, and many more to better my working setup and reduce hand movement, including putting mouse controls and pretty much all shortcuts in my keyboard, I would not have been able to continue typing until the end of my semester. However, that made me realize that the thing that helped me the most is that other than my arms, I had 0 other issues. My mental health was in check, I was with a reasonable diet and I managed to push through to my holidays, where I managed to get a meaningful solution to my problem (which was physiotherapy).

I am sure that a split keyboard, or even a programmable ortho keyboard that is well planned with a good layout and ergonomic position can be a great help, but what helped the most was the ability to adapt my setup, my self and my surroundings to my pains and specific problems again and again and the motivation to stand through it until the end. To study it, see what others said about the solutions, and try them myself. A lot of times those were slow, tiring and saddening, but I knew it had to be done and it paid it's dividends for sure

You should look into an ergo keyboard, which is even better to start when you have little to no pain (better stop before it gets worse!), but know that the best thing that you can do for yourself isn't just buying a new keyboard, but also taking care of yourself. The new keyboards didn't immediately solve my problems. In fact, adapting to them made it worse in the short term, but after ~4 or so months of pain, I have a stable setup with a nice keyboard that allows me to work with reasonable comfort again, and that is half in part thanks to the keyboard and half in part thanks to me taking care of my heath regardless of how hard it was sometimes.

Thanks to that care and all of my steps, it looks like I'll have no lasting consequences if I finish up physiotherapy and start training my muscles properly, which is the best news I could've had. The best advice I can give to you (and to my past self) in order of importance (in my opinion, see other's too!) is 1. Be patient. 2. Listen to your body, take breaks before you need them. 3. Exercise more 4. Make your setup more ergonomic, be it with keyboards, chairs, positions or whatever else.

I am aware that my case is different from most here, as my wrists are as health as they can be (I don't have issues with ulnar deviation causing pain, the shoulders are fine, everything is good except for the extending and retracting of fingers), so my issues and solutions were quite unique to my case and because of that I won't go into specifics, but I hope to have managed to at least show one more perspective. Keyboards help a lot, but in the end it's yourself that can help you the most.