@Mary14....try to remember that recovery for joint replacement surgery can easily be a full year to get all the kinks worked out. Some people require even more time, so please don't give up. The MUA will set that knee back a bit in recovery as well, so realistically you should probably count both knees as starting the recovery process at the same time in October.
Your first priority is to relieve the pain. As Jockette mentioned, that is likely the bursae that is causing that. You may also have some IT band issues that is causing the feelings you're having on the outside of your legs. When you see your surgeon again, ask to see if he would prescribe some therapy for you.
I'm happy to hear that you have good range of motion to both knees. That's usually the biggest hurdle to overcome. The stairs are always challenging for a while, especially if a person needs to rebuild strength in your leg muscles, which you probably do. Therapy can help with that as well. Just be sure that you are never exercising or doing activities that result in pain while doing them or in the 24 hours afterwards. That is counter-productive to your recovery and will keep your knees inflamed.
I wouldn't be surprised for a therapist to discover that the stiff legged walking is a gait issue and it can also be helped with specialized gait therapy. You might consider trying the
OneStep app that we offer here on BoneSmart (you should see a link either to the side or at the bottom of your screen or use the link I provided to learn more about it. If you want to try OneStep, register from the linked page and you can get a 2-week free trial and a 15% discount for up to 6 months on the program by using the promo code you'll be given when you register.
It isn't unusual for people to have to "relearn" proper gait after joint replacement surgery, so don't think this is something that you'll be stuck with forever. It took a long time for your knees to get as bad as they were and recovery can be lengthy as well.
We're here to support you and answer any questions you may have. Please don't hesitate to post if you have a concern.