Thank you for your response both were helpful. After another serious ER visit I finally got a referal to a neurologist for an MRI. My cat scan at hospital was normal so I hope an MRI can help diagnose me.
My MS expert at a prestigious university hospital said the average age of onset of MS is 28. Thirteen would be considered young, but certainly not 29.
Balance problems, vision problems, and extreme fatigue are common signs of MS. If current doctors are dismissing you, find a new one and start from scratch. Your symptoms alone warrant testing.
You are not too young for MS by any means. If your mom is nearby maybe you can get in to see her doctor, but regardless you need to have a PCP that listens. You may not have MS -- other things have similar symptoms, as your mom learned -- but you do have something that warrants attention.