Hyperextended knee

Hi.
About 4 months ago I hyperextended my knee during a softball game. My knee then would not bend properly when I walked and it was painfull to bend. I then saw a sports docter and he diagnosed it as a LCL sprain. I was on crutches and a knee immobilizer for the first month. I went back and the pain was still there so he sent me to a physical therapist. I went there for a month and it didn't get any better or worse. So I went back to the docter and he ordered an MRI. The MRI showed a tibial plateu bone bruse and a bruise on my femur. So the docter put me back on crutches for two more weeks. Then I went back, and it still hurt to bend. He then said he was contemplating a meniscus tear. He sent me to another docter for a second opinion. I went there and the 2nd docter then ordered an arthroscopic surgery. I hd my scoping done on May 25th and they didn't see any cartiledge damage but they took out an orthoarthritis lump.
It has been about a month since the surgery and it is still painful to touch, run, and squat. I can bend it now with minimal pain but why is it still hurting on the lateral side? Please if you know give me some advice.