Knees have clicked for years, 2 weeks ago I hit my knee against a barrel at work and then when I bent down something in my knee cap pop, extremely painful, it's happened 3 times in the past week, was limping around then knocked it at work it killed, I went to gp and he told me he thinks I've damaged my cartilage, not to bend it, take ibuprofen 3 times a day, and to go back in 2 weeks if no better to get scanned, it's got worse, pains worse and constant, looks slightly swollen and bruised