I may have injured my knee, i feel pain when straightening and locking out leg

[Jmek]

I had to take a week off training because of flu. During this time i first felt like my quads were very tight and kind of pulled my kneecaps, after that resolved itself i felt pain on the back of the knee around the meniscus. This pain really feels when i straighten my leg while walking, it doesnt happen when i go downstairs or upstairs unless i fully extended my leg. So straightening my leg to a lockout produces this pain. Also my legs feel kind of unstable in the morning its weird to describe, almost like there is some fluid in them. They dont seem to be swollen but kneecaps feel a bit floaty and "inaccurate" in the morning, twisting the legs hurt but once my day starts properly they start to work normally and feel more stable. The lockout pain however is there.

I also sometimes feel pain in hamstring tendons but this is not as often as when locking out/straightening and then loading the leg with weight.

If i do squats with just my body it doesn't seem to worsen the situation so i am looking forward to continue squatting once this flu is over albeit not with the same weights i used before.

Could this be a piriformis syndrome?

When i stretch, foam roll or squat without barbell it doesnt seem to worsen the situation. Once i get the blood flowing and muscles working it seems to help but so far it has been temporary, i do some foam rolling and stretching every day now hoping it will solve this. There is no pain when squatting with just my bodyweight, however if i straighten my leg with speed to a lockout it does produce pain around the meniscus/back of knee.

Situation has been this for about a week now, its very annoying when walking to feel that pain when i straighten my leg. Right leg is more suspect to this than left but at first left was painful too but it stopped after a few days, right leg has not sorted itself out yet and i am not sure if it will.

[veryhrm]

If it didn't happen while you were exercising or with a specific event it's probably just flu related. Doesn't really make sense that your knees would get a genuine injury while you were sleeping or watching tv.

My last bout of the flu caused my skin to hurt all over for a few days.

So i'd say take it easy if things feel swolen in there, but don't worry about it yet.