I Fell 3 Weeks Ago Tomorrow And Have An Effusion.

I fell 3 weeks ago tomorrow and have an effusion. I went to er where they x-rayed it and said it was a possible acl or patellar tendon tear and I should follow up with orthopedic. After visiting orthopedic, and spending less than 5 minutes with them, I was told stay off of it and do some exercises and come back in 3 weeks. I have noticed no change in swelling, pain and my ability to walk is only slightly better. Is there something else going on or does it just take time?