Long run! Awesome that you got through it even though you weren't feeling it. Building that mental strength will help a lot in the future.
As for the knees - where is it hurting? Do you have strengthening stuff to help?
it slightly hurts kind of around the kneecap and the sides - it's not that bad, I really think it's just fatigue and that I gotta strengthen it, even though I'm not sure how. Tbh my hips hurt more, but I know what to do about that and I've been trying to do things for that and they've been definitely helping