It is possible that the C5/6 disc bulge could be causing some of your symptoms, but does not explain the leg and buttock pain as well, especially if it is just slight. Something in the lower back like a disc herniation there sounds more plausible as the cause of the leg and lower back problems. A helpful test to evaluate the integrity of your muscles and nerves would be an EMG or electromyogram where they send little shocks up your nerves and then put needles into the muscles. This will help to see if there is any nerve damage and localize the problem to the spinal cord, nerve roots, actual nerves, etc...
A second opinion may also be helpful for a fresh look. Finally, depending on when you had the MRI, a repeat may be necessary if significant time has passed. Good luck.