Most likely what you are suffering from is not nerve related but related to your joint . At your age this can be a mild variant of Patellofemoral arthritis , that to early stage. Just take basic analgesics for a few days along with good Physiotherapy and Knee cap support . You should be fine
Next Steps
Physiotherapy with knee strengthening exercises
Health Tips
Do not Squat , Do not sit cross legged , Avoid using stairs ,