Greetings, sorry about the pain. you have spoken at length about your concerns but didn't elaborate on treatment criteria followed with physiotherapy.
Your problem is more of lack of strength in muscles and nothing else. Once you get your strength back you can run stairs or jump and do whatever you want.
Swelling and pain will be taken care by balanced diet and structured physio program. See a dietitian to get your
uric acid sorted.
Next Steps
hire a physio as your personal trainer and get yourself trigger point therapy and exercise program for minimum 3-4 months 4 days a week and you should see results in 10 days and get to normalcy in 3 months.
Long standing hours is something not to be worried, just follow exercise program for 3 months and thereafter make exercise as your habits then see the remarkable change in you for good.
Health Tips
if unable to get results or could not find physio to help let me know will assist.