Shirleyw
I started c25k last October. I had many set backs and did many weeks more than once. Just before lockdown, for some strange reason I started again and completed it on 24th May so it took me 7 months!!
I then did what they suggest which is consolidation runs for about 9 runs, by this time I was running 30mins 3 times a week. No way was I running 5 k but so what?
Had a break in the summer when family came to stay and am now back to trying to run 3 times a week but usually not succeeding as I work full time so if I can run 3 times a fortnight I feel I am doing ok!!
Apart from the lung problem, I have rheumatoid arthritis, fortunately not so bad that I need medication, 2 prolapsed discs and severe wear and tear in my neck (work related)
I have tried yoga, pilates and tai chi, all of which I ached after but for some strange reason, running is fine and causes no pain except from the odd sore muscle. My dodgy ankle can start to ache before a run but seems to be fine after?!
Have you looked at 'Health unlocked ' on line? Lots of information and support for those doing c25k.
Good luck, make sure you don't run 2 consecutive days and always stretch after a run.