Weed post surgery

I had meniscus surgery back in mid August. I wasn’t pain free until late October. However when I would smoke after my surgery and even now, I feel this tenderness in my knee. It’s weird because when I’m sober it feels like my knee is as good as new. Now its almost like I can feel the incisions underneath my skin. Doc said there should be no stiffness anymore so idk why I can feel it when I smoke. Anyone have an idea on why this is or have experience something similar?