Uncomfortable knee cap

I'm 8 weeks + 4 days after a PKR and for the last 4 days my knee cap has been feeling really uncomfortable and feels like it's catching on something, which causes me to limp. It was resurfaced during the op. Has anyone else experienced this? 

Yes, I get this sometimes, but it doesn't really make me limp . Just feels as though it clucks against something 

Pam 19 weeks 

Mine sometimes feels like it's slipped down and catching on something. Sometimes it really hurts. My physio thinks it's scare tissue, she's giving it until Monday and may refer me back to my consultant. 

Have you experienced this at all in the first 8 weeks or is it a brand new symptom? If not, there could be something that aggravated it.

It seems to have started just recently, the only thing I can think of is I've started driving again so maybe it's that