As patients, we naturally assume our medical professionals know what's best for us, and know every detail of the recovery process. But, the truth is, while most are there because they want to help others, many of their processes are outdated at best, and very wrong and harmful at worst. Every patient is different, and heals at a different rate. Heck, two knees on the same person heal at different rates! Only the patient actually knows what is helpful and what is harming us because we are the ones living with the result of the surgery, PT, and so on. Only we see our knees swell excessively after an aggressive PT session. Only we feel the new pain that comes after a PT session that was more than our knees were ready for. Trying to generalize recovery stages for everyone is counter-productive and can be, IMHO, very harmful to patients.
Instead of giving time frames for recovery steps, it would be much more helpful if surgeons, and others, gave their patients info about recovery stages, but no timelines. Instead, they need to say things like, "At first your knee will be stiff, until the swelling goes down". Or, "You will most likely be unable to lift your leg at first, but at some point in the first weeks you'll find it just happens and you'll lift your leg again without trying. Until that time, don't stress as it's a very normal part of the surgery and recovery". Or, "Your ROM will be low at first, but over time will improve as your knee heals and the swelling reduces".
These are all helpful statements, and allow for the individuality of recovery while not stressing out patients with deadlines and threats.
As for PT, it's YOUR body and YOUR recovery and only you have the right to decide how it will go. Others may make suggestions, but no one; not your surgeon, your PT, your spouse, your family, or anyone else, has the right to tell you how it will go or what you will do. Just because your surgeon fixed your knee does not mean he now owns your knee. This doesn't mean that others won't have helpful suggestions, it means that YOU, and only YOU, make the decision as to what you will and won't do during recovery. And your knee will loudly let you know what it's ready for, if you will listen to it.
If PT is causing you more pain and/or swelling, then it's your knee telling you it's not ready for that activity yet, so back off and re-visit it at a later time. IME, PTs are a mixed bag; some are great and follow a process that leaves you and your knee in charge, without causing any more pain and swelling. But too many are overly aggressive, and insist on being in control of YOUR body and YOUR recovery, using pressure, threats and intimidation. My suggestion is to either find one of the former, or stop formal PT altogether and just do the ADLs.