I would just observe the dog for a few days and take it easy. If the limp goes away, I wouldn't worry too much about it. If you have a Whole Foods nearby, go and get some Traumeel. It's a homeopathic remedy for muscle sprains and things of that nature.
With panosteitis the most commonly affected bones are the radius, ulna, humerus, femur, and tibia, though the foot and pelvic bones may also be involved. The dog will respond to direct pressure on the affected areas and he may show reluctance to walk or exercise. From what you describe, it doesn't sound like it's pano.