I'm 44 years old, in good shape and pla hockey 1-2 times a week. After last weekend (Played three games in two days) my left knee started hurting. First on the top (outside), then lower on the (inside), and now the back (outside) going into my calf muscle is sore. I also have pain/pressure when I "lock' my knee straight. Not terrible pain but noticable. Any ideas? No previous injuries to this knee.