Okay in the cold

Saturday's long run was much more comfortable than I expected, given the low temperature and wind. I've recently picked up some cold-weather gear on sale - really the first I've ever owned - and it seemed to work pretty well.
For the single-digit wind chill I dressed this way:
Two pairs of socks.
Cold-weather long-sleeved shirt.
Two more long-sleeved tech shirts.
Wind-breaker jacket.
Tights.
Cold-weather technical pants.
Heavy gloves with hand warmers inserted
Moisture-wicking balaclava
I didn't carry anything to drink, since it tends to freeZe or get so cold it's hard to drink. Instead, I placed a bottle of Gatorade in a cooler in the back of my truck and looped back to it every 3 miles or so for a drink.
My plan was to keep moving and to avoid running into the wind as much as possible. The wind was out of the west northwest, and I was lucky to have a route that never forced me directly into it.
I did 12.25 miles, and in the middle part of the run I had the feeling I could keep up my 8:40 pace indefinitely. It never really works out quite like that, but it's a nice feeling to have anyway.
I did have a problem at about mile 10 that is a bit of a concern. I've experienced this before: a "catch" in my ankle joint. To me it feels like a bit of calcium breaks away and gets in the joint, then hurts like hell until it works free. Usually, it works free in a minute or two, but this time it stayed with me for two miles. By the time I got home and took a look, my ankle and all around my lower leg was puffed up, stiff and sore. I've had limited range of motion all day today.
The pain in my ankle caused me to slow down considerably in the last two miles, but I still averaged 8:52 for 12.25 miles. Now, though, I probably won't run for several days while everything heals up.