Knee pain when walking on flat ground

Hi,

I do not work out and don’t usually go to the gym or participate in sports. I keep active thru low impact dance classes and casual walks around the block.

I woke up 2 days ago with my left knee area hurting when I walk. I can’t take more than 3 paces before it starts hurting. I can’t pinpoint the pain as it seems to encompass the front, sides and back of the knee up my hamstring to my tailbone. Nothing hurts when I touch my leg, knee or back. I can bend and flex my leg with no pain when I am sitting down. But it hurts when I push off with the leg to take my next step with the other leg and it REALLY hurts to go down any type of slant. If I lock my leg straight, there is no pain. There is no swelling and no pain going uphill.

The only thing I can think of doing is wearing a pair of high heels for a day. I don’t recall straining or pain after.(I’m usually in heels much flatter than 3″)

Also, my right knee has had problems that the doctors can’t seem to fix for over 4 years now and I usually depend on my currently hurting left knee for most of my support.

Can someone please tell me what’s going on (and hopefully that this will go away) or will I end up with two bad knees for the rest of my life?!

Thanks so much in advance.