no, for christs sake, do not go to a doctor. Not a GP anyway. If you have any means of seeing an orthopedic specialist, then thats fine, but your average GP does not know a fucking thing about musculoskeletal injuries. Its not their fault, its just that that shit takes a back seat to medical problems in their training.
Im a physiotherapist (physical therapist if your from the states). I could tell you all the symptoms, but without actually performing an examination, theres no way of diagnosing your problem.
Odds are you dont have an ACL rupture, because they are very traumatic and you would be unable to tolerate more than minimal weight bearing without feeling as if the knee is going to give way.
But you may have done ligamentous, cartilage or meniscal damage.
Go see a physical therapist or an orthopedic surgeon. A doctor will just give you a prescription and tell you not to ski.