Hoping that it's not too serious.
In the past, Tim has said that he acts like a baby when he's in pain, so his being immobile after he went down doesn't tell us much.
On the other hand, I've had tears in both knees and lots of bad ankle sprains and was able to leave under my own steam. So his walking to the dressing room doesn't say much either.
We'll just have to wait and see.