A Sprain is a tear....it's the severity that matters. Grade 1 through 3, with 3 being a complete rupture that can only be fixed with reconstruction.
(Sprains are tears to ligaments, Strains are tears to muscle/tendon)
ACL is EASY for a physio/Athletic Trainer/ortho to test. Can literally figure things out in less than a minute provided your hamstrings aren't crazy tight and resistive to the testing.
After hearing your history and the mechanism of injury, the 2 main tests are the Anterior Drawer and Lachman's drawer.....no you can't do them to yourself (even if you know what your are doing).
The MRI is used to confirm but remember something like a 95% accuracy level using the ACL tests mentioned. They'd also perform PCL tests (like posterior sag and the like) to also check PCL quality....although even if ruptured, the PCL doesn't get reconstructed....not worth it as it's function is limited anyway.
Go see somebody that specializes in sport medicine. Didn't get where you live, but pretty much all University's/Colleges with sport programs have MANY qualified professionals to assist. There usually is a sport med clinic on campus. Even a 1st year physio student could figure it out. If that fails I'm sure the National Athletic Trainer's Association (NATA) should have a database of it's members you can search.
I used to be a Sport Physio and Certified Athletic Therapist/Trainer (Trainer was my American equivalent through the NATA which I held membership with as well) (as well as an Exercise Physiologist) in a previous life, working with a number of national programs up here in Canada if that provides any context.
There is a simple test you can can do with a help of a friend, it's called LELLI. if your ACL is gone it will be positive.