Thanks for writing your query.
After reading your post, it seems that you might have suffered from soft tissue injury
Still you should get an X-Ray of your knee done and get yourself examined by an Orthopedician.
You should use a knee support. Local application of pain relief gel will be beneficial.
You can take painkiller like Ibuprofen
twice daily after meals along with an antacid
40 mg once a day before meals.
Give rest to your knee. This will help in healing quickly.
More can be planned after knowing the X-ray reports.
I hope this is helpful to you.