Hello doctor and take you for taking time to listen to my problem , i noticed that i'm having a lot of problems with my legs , my knee makes cracking sounds whenever i do squats , my legs start to shake whenever i get tired after working out or walking for so much , and i can't find any comfortable position to sit on when i sit on the ground , i used to sit down normally now i have to stand up because my legs either start shaking or i get pain or i can't even hold some positions