I fear for you with that doctor. He appears to be useless.

At a minimum you want the fluid aspirated and you want the knee checked to see if you have an infection.

Yes, it can take a year (even more) to get to a fully functioning knee but that doesn't mean that the doctor has no duties to deal with issues that come up during the recovery.

Are you in or near a big city? You need a good revision surgeon to advise you (by good I don't mean one that always wants to cut).