My right knee was sore over the weekend a week ago, but it felt fine all during the week. Just before I left for my run I was bounding up and down the stairs in my house, and I expected to have a great 5-mile run. However, as soon as I started running I could tell my right knee wasn't up to a great run. The knee had no pain or soreness. It just felt weak as if it wouldn't support my weight. The knee felt fine when I was walking. As a result, I reduced the length of my run and completed 3.5 miles at a relatively slow pace.
The temperature during the afternoon was in the low 40s (F), and it was in the mid 30s when I left home for my run. The temperature was 33 when I returned. The sky was clear, and there was lots of sunshine during the day. I ran in the late afternoon, and the sun set while I was on the return leg of my run.
My tailbone isn't completely healed, because I can feel it when I do my situps. As a result, I don't have as much movement in the situps as I usually do. Other than during the situps, I don't have any pain or soreness in my tailbone. My back feels fine, and I think it is completely healed.