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I have read your question with diligence.
It looks from your details that most probably you may be having injury to meniscus of your knee.
Meniscus are structures which act like cushions when we bear weigh over the knee.
Presence of locking is diagnostic for that.
MRI is diagnostic, get it done when you can. Till then you will have to rest your knee. Do not do activities that put pressure on your knee like squatting, kneeling, twisting and pivoting, repetitive bending (eg, stairs, getting out of a seated position, clutch and pedal pushing), jogging, exercise classes, dancing, swimming using the frog or whip kick, and bicycling.
If the pain or pressure is your leg is too much you can take the OTC tablet Ibuprofen 400 mg when required.
After MRI is done and a definite diagnosis is made, based on the scan results you can begin straight leg raising exercises without weights as the pain begins to wane with the goal of strengthening the quadriceps and hamstring muscles to provide support to the joint
If this tear is large then this should be treated by removing the part of menisci.
Location of tear at menisci at different part also change the mode of treatment.
Till then protected weight bearing and ice fermentation will help you. Yes remove your braces and do ice fermentation for 15 minutes 3 times a day. When you are resting, keep your leg elevated.
Hope this will help you.
With best wishes.