Have pain in left knee and clicks now and again but at the minute i feels like its grinding and even when am not doing anything i get pain?

Meniscus: This is unusual for arthritis. You are quite young and unless you have had trauma the most likely cause would be internal derangement with the most likely being a meniscal tear. See your ortho doc if possible and get a better opinion. Best wishes.

Orthopedic surgeon: If this is a persistent and uncomfortable knee problem,I recommend a visit with an orthopedic surgeon who will delve into the situation with thoroughness. It may require an mri to look for cartilage damage or inflammatory disorders of knee structures. Physical therapy and antiinflammatories May be needed but not necessarily surgery.