I'm so sorry your surgery was postponed. I know what that feels like; my revision a couple of years ago was postponed for a few months due to an injury my surgeon suffered and had to have repaired. Plus, my recent surgery had to wait about a year due to us moving to a new home; then when I was supposed to get it scheduled for last spring, everything shut down. I was also worried this one would be postponed, but this time I was able to get it done.
I'm sorry you lost your friend.
Here's my advice.................First, stop asking google to diagnose your pain-all it will do is scare you with multiple wrong diagnoses. Then, if the pain persists, message your doctor to be safe. In the meantime rest that knee as much as possible, and maybe try icing it. Just remember to keep a cloth between your skin and the ice. When you have bone-on-bone and/or painful knees, sitting in chairs can really hurt, so avoid doing so for at least a while.
I went into my kitchen this evening and sat down in a chair; what a mistake that was. After a minute or so I was in a lot of pain and could not stand back up. My husband had to help me up, and it hurt like

to do so. Although for different reasons, chairs seem not to be friends to either of us right now.
I hope your surgery gets rescheduled soon-it's no fun to be in pain and not be able to get it fixed.