I did some research online about this slow down and discovered that it's not all in my head. For many people who have had total knee replacements there are new aches and pains around the third or fourth month after surgery. Nothing serious but they don't see the progress of earlier months.
My complaints typically were not around the surgery site, the left knee, but on my other side -- my right leg, foot and lower back. At any rate I've been sore much of the time and used it as an excuse to avoid going to the gym. And yet when I did go to the gym, even if to simply ride the bike for a few minutes I felt better. But it is so easy to put it off until tomorrow. I must make going to the gym and doing the knee exercises my top priority.
Much of my physical problem is the lack of balance between my weak left side and my stronger right side. Again, this will improve with more gym visits.
I did stay away from doctors all month. Except for an unrelated exam by my primary care doctor when I developed a big blister from a spider bite.
As for the knee replacement and the area around it, it doesn't slow me down. There's rarely any pain at all. It is swollen a lot of the time, especially after exercise or yard work but other than looking weird it's not a problem. I need to ice it more I guess.
The weather in the early part of the month was quite warm and I got in the pool on May 13 for my first swim of the season. The water was quite cold, but bearable. The rain later in the month made the pool colder still, so we haven't been in again. Usually we are in the pool daily by mid-May.
On May 19 we took a road trip. The longest for me so far. We drove to New Orleans, 200 miles each way, with lots of stops for stretching and changes of drivers. I felt great that night and the next day but on the second evening my right leg was quite lame and my lower back was bothering. Probably it was the long time sitting in the car and too much walking in New Orleans' French quarter. There's a lot of rough pavement and I was leaning on the cane pretty hard.
In the morning it was difficult for me to walk but there was no problem driving. Because of bad weather en route we left for Pensacola mid-morning.
Regardless of my hobbling around the French Quarter, New Orleans was wonderful and their recovery as a tourist destination is coming along very well.
A week later I am better but still lame on my right side.
[Aside from my medical complaints, this month we also lost the old air conditioner and heating unit and had to get a new one; the pool was infected with green algae and has taken most of the month to clear up, with much fussing with filters and adding nasty chemicals; and two days ago the house was struck by lightning, again. It was the second strike in five years. This time the lighting strike fried all the outdoor electrical circuits including the pool pumps, but it spared the new air conditioner compressor. We look forward to a long time without visits from salesmen, estimators and repairmen.]