fell on knee

[lefty16]

I was playing softball on saturday, did a headfirst dive into 3rd. Never had any problems doing this before, but this time when I stood, my knee hurt and felt really unstable. I guess i landed on it first.
It was bad at the time, has improved a lot, but when i fully straighten my knee i get quite a bit of pain. I also get pain when climbing stairs.
Any ideas?

[Heidi]

Hi
It could be any number of injuries. As it has only been 3 days, continue to rest and ice and if it hasn't improved by the end of the week then make an appointment to see your Doctor.