Knee pain could be due many reasons, which could be established with detailed history, physical examination and relevant investigations. In you case, X ray are essentially normal.
Next Steps
Visit orthopedic surgeon or consult online
Health Tips
• Active Joint Range of Motion exercises-Full flexion/Extension to be achieved at 1 week, followed by Static and Dynamic Quadriceps/Hamstring Exercises.
• Watch for increased Pain/Swelling/Stiffness/Redness/Fever. If present, visit the nearest hospital immediately.
• Avoid ground-level activities like squatting and cross-leg sitting. Use English/sitting commode for toilet activities.