I have to agree with the previous posts. I will also add that you can perform your own physical therapy. Nothing straining though. You do not want to injure yourself any further. Find exercises that you can do on your floor without the use of gym equipment. Strengthen your quad, thigh, hip flexor, calf and butt. Building up the muscle tissue may aid in the recovery standpoint, but it isn't an overall cure.
You do absolutely need to find another Dr. A knee specialist. Yes, it may not be cheap, however do you feel like you want to live with chronic knee pain knowing that you could have fixed it earlier? I've been in pain for 2 years because I listened to 1 Dr. and never got a second opinion. See the same Dr. who told you your meniscus was torn and ask him to show you on the MRI. Also, ask him if there is any other way to interpret the information on the MRI. As the previous posts suggest, it's not likely that somebody can miss-read and MRI however, it is possible to see an injury differently. That is, every Dr. diagnoses differently. It, after all, is the Dr's opinion. When all is said and done, get that 2nd or 3rd opinion and go with the Dr. that you feel you can trust. I hope this helps, best of luck!