Replying to Dr. NS: Did I tear my ACL?

I was skiing two days ago on snowflex at Liberty mountain in VA.  i attempted to land a 720 degree spin, but was too far backseat when i touched down.  my left ski caught an edge and the nose shot out to the side while i continued to twist and fall the other way. i felt serious pain, and then slid down the landing and could barely stand up.  here are my "symptoms",  if you have experience with knee injuries, tell me what you think.

-i DID NOT hear a "pop."   i talked to a kid who tore his acl last year and that was the first thing he asked me.  he also said he felt a jolt go up and down that whole side of his body when it happened, which i did not really feel.  these two things are making me most confident that i did not tear anything.
-I can bend and extend my knee.  I have to do it very slowly, but i can move it straight back and forward.  it is very painful, but my friend who tore his said he couldn't do that for five months after his accident.
-any sort of sideways or twisting pressure is extremely painful, like if i step on it the wrong way, i literally cry out in pain.  if i keep if perfectly straight i can walk slowly, but sometimes i dont think about it and my leg gets a little off center, and it is terrible.
-this is my least favorite part,  its getting worse.  on saturday when it happened i could walk much better than yesterday, and like five times better than i could this morning when i woke up.   when i have hurt my knee before, i could usually tell that it was slowly getting better, but this one seems to be going the other direction.

so NS, those are the facts.   i really dont think its torn, but since alot of skiers have this problem, i figured some of you could help me out before i decide to go to the real doctor to check it out.