Introduction. Sudden pain in one of the knees is usually the result of overusing the knee or injuring it. In many cases, you don't need to see your GP. The knee joint is particularly vulnerable to damage and pain because it takes the full weight of your body and any extra force when you run or jump.ou should see your GP if you think the cause of your knee pain is gout. They may recommend using ice packs and taking non-steroidal anti-inflammatory drug (NSAID) painkillers. You may also need to change your diet or receive additional treatment to prevent attacks if you experience them frequently.