Knee Pain on Inner Knee (Recently switched bikes)

I'm trying to do the normal self-diagnosis thing first. I switched last week from a road bike to my first tri-bike. I've been a marathoner and distance runner for the past 12 years so I'm fairly well versed in running injuries and issues and I'm not sure this is one of them. I did a professional fit on the tri-bike about 10 days ago, and did my first training ride on the bike Sunday (only 25miles). On Monday morning I was going to go for a run and I felt some pressure/irritation on the inside part of my left knee (ITBS typically on the outside, this was on the opposite side), when I would push off with the ball of the foot. My previous run was a 7 mile run 3 days prior with no pain or discomfort. The only change has been the addition of the tri-bike instead of a road bike. I'm trying to figure out if this could be due to the fact that now I'm riding in a different position and my body is just going through the usual aches and pains of doing something different, or if it might be something like needing to adjust the fit of the bike or maybe an issue with crank length. There is no pain when I'm actually on the bike, only when I'm pushing off with the left leg. Yesterday morning I went out for a 10mile run, there was some "pain" here and there for the first 4 miles or so, more like an annoyance (but much less than on Monday morning), then the last 5-6miles there was no problem. I then went out for a 2 hour ride last night and left great, but I can tell that if I was to start a run today, it would start with the same feeling in the knee initially. Any help/suggestions are appreciated.