Just stand up and take a deep breath and say, "Hi, I'm Blessings and to the best of the medical industries knowledge they "think" I have MS." Then sit down.

That will be enough to get everybody started anyway.
When people would go off and start their whining and complaining I would simply sit back and say very quietly, "Those are very good points. Now that we know what they are in your case, what are you going to do to change that?" I always felt a support group was a place to meet people in a similar situation and somewhat like minded looking to better themselves or their situation. I always told them, "This is NOT the Dr. Phil show."