I twisted it as my knee was locked playing soccer last week i have been wearing a knee brace but knee is bruised and sore should i play or sit out ?

Knee: It would not hurt to see your PCP or an Sports physician before you play again to rule out serious internal damage.

Please get examined: With continued pain after a trauma, a physical exam and possible imaging studies are necessary to evaluate your condition. Bruising and soreness is a sign of an injury. At your age, I would get checked by a professional before going ahead and doing high impact activities.