When I blew mine out I had three doctor's visits.
First to my general practicioner or whatever it's called. He recommended a specialist. So then I went to a knee/orthopedic specialist. He recommended an MRI. So then I go get the MRI and I had an ACL tear. So I'm not sure if there's a way to skip one of those steps or what, but it'd be nice to go straight to the MRI. The MRI costs over a grand, btw. I think in the neighborhood of $1500. I should've gone to school to be a radiologist.
My pain and swelling lasted several days.
What you really want to avoid is miniscus damage. That can't be repaired. They can cut away the damaged part, but they can't put any back. I left my ACL torn and wear a knee brace for hockey, but leave it off for everything else (basketball, soccer, motorcycling, weight training, etc.).