I think I posted this on the other topic you started about the knee- but try RICE first. Rest (cut back a bit on activity), Ice (ice 3x a day for 20 mins each time), Compression (wrap the knee or put an ace bandage on it), and Elevation (elevate the knee). Also consider an antinflammatory.
Work on strengthening muscles around your knee- lift with activities that focus on strengthening the quads, hamstrings, calves, and core.
I had really bad knee pain and popping after running last month and worked really hard to strengthen the knee with quad exercises. I iced it religiously after working out and then 3-4 more times throughout the day. I also took ibuprofen on occassion to also relieve the inflammation. Knee is back to normal now
Minor pain can often be treated with home treatments. If it doesn't get better in a couple weeks, go see a PT or orthopedic surgeon.