Brief Answer:
suspected arthritic conditions in and around the knee joint...

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concern...

Well, if this is happening only recently, then it could be related to some trauma/pinched nerve/muscular weakness of the lower limbs which could have worsened overnight...However, if it's happening on-off, and there are any back issues as well, then there's a possibility of arthritic changes or nerve entrapment of the spine (spinal-disc) and in and around the knee joint...

Either way, this should be evaluated further by an Orthopedician along with a few investigations (An X-ray of the knees and hip joints, blood investigations i.e. Hemogram, U&E, Vit D3, Vit-B12 levels, Uric acid, ESR to look into it further)...

Management is basically depending on the findings, however, comprised of nutritional supplementations (whichever is found insufficient), pain-killers and physiotherapy, and corrective surgery (only in advanced cases)...

Please discuss this with your doctor and proceed further...

Meanwhile, please don't use Advil beyond 3-4 days, you may continue Tylenol (it can be taken round the clock 650mg up to three times daily after some food)...

Apply some dry heat over the area...alternate hot-cold compression gently along with careful massaging would be beneficial to some extent...Please avoid weight bearing on the feet as much as possible for the time being...Perhaps keep the limb a bit elevated and stay rested till further evaluation...

Let me know if I can assist you further.

Take Care
Kind Regards

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