Strange knee pain - any ideas?

[suiledonne]

For the last few days my knee hurts when I kneel down - like I am kneeling on something sharp. Not in pain with it although it sort of feels warmer on the inside IYKWIM

I have an 11 month old crawling dd2 so seem to spend a lot of time on the floor with her these days.

Any ideas what it could be?

Oh, how my DH will laugh. Just googled. It sounds like housemaid's knee. There was never a less likely candidate for a housework related injury than me.