Where is most of the pain located for an ACL tear?

It is certainly possible. That medial pain can also be torn meniscus, however torn ACL's usually result medial meniscus damage as well. That could be what you are feeling as I was before my surgeries. The ACL cannot heal itself, some of the other knee ligaments can. Go see an Orthopedic Surgeon and at least get an MRI. Better to fix any damage now than pay later in life with an artificial knee.