Get it scanned - the NHS (at last) seems to be 'sweating the resources' and has generated some spare MRI capacity - my friend had to wait less than a fortnight for a knee scan & they're doing it on a Saturday afternoon. Your GP should be able to refer you.
Well...if it is "locking" in one position or suddenly "letting you down" then i would agree with rowan, but if it isn't then we may be looking at a loose body or indeed a number of things.
I agree with Dr Rowanwitcht idea go to see your GP before the pain stops you from being able to walk.........................................
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It doesn't let me down. Just a bit sore and clicks. The click feels like it's coming from the back of the knee. I just worry that click is going to snap.
It was the "old injury" statement that prompted my suggestion of scanning - obviously a new problem wouldn't need that (or even a GP visit) unless/until it didn't respond to NSAIDs.
My knee 'pings' constantly from a previous injury but in a different place. If you don't want to take painkillers, maybe you should strap it up. I know it helps my knee if it gets bad.
I don't mind doctors. I just don't like to bother them unless I have to.
Like I said in the OP, it's not overly painful, but it's constant. I just don't want to damage it further. I'm 38...I still want to fight the kids and race them to the shop...and do stupid stuff with them.