What Causes Lingering Pain In The Right Knee?

Good day and thank you for taking my question. I m hoping an orthopedist will be able to give an answer, if possible. I m a 38 year old soccer player. After one pretty tasking game, after my body cooled down when a team mate dropped me home, I felt a lot of pain right under my right knee cap. It only hurts at a particular angle when trying to sit, squat or get up. I d say approximately between 55 degrees and 35 degrees. After a few weeks of avoiding sporting activity, the pain reduced significantly, but is refusing to completely go away. I am trying to figure out what it could be, being that I didn t have any collision or bad bend/twist or any kind of hyper-extension. There is no other pain when applying direct pressure to or around the area. Also, this is the first time this has happened. I ve been playing soccer for years. Your advice will be much appreciated. Regards, Dmitry