15 Day DL already?

Last night I worked til 7 p.m... another late night. However, I couldn't decide if I was being a dedicated employee or just avoiding the gym. I eventually made it there (thanks to some girl scout cookies and an ice cream cone feast at work.. bad Kim), and hit the treadmill. I managed 3.25 miles, which assures me I can do the running leg of the triathlon, but I am worried about my nagging left ankle soreness/injury. I have no idea where this came from, but it's been sore and stiff for a couple months now. It was the worst it ever felt running on the treadmill last night. I hope an ankle brace will help and I won't land on the 15 Day Disabled List!