Diagnosed with CIS

Hi, last week I was diagnosed with CIS and still reeling… A short synopsis. I am 47. I have had a stiff back for about 25 years, terrible migraines and bouts of uveitis which started about 13 years ago. I had a scan for back ache which showed up a lesion on my spine. This was followed by a brain scan which showed up multiple lesions. I had electric shock feelings in one leg during summer. Because of all this the neurologist declared I have CIS. He has requested a lumbar puncture and head scan. Why would I be sent for head scan when I’ve already had brain scan? Can anyone tell me about their experience of CIS.How long did it take to progress to Ms, if it ever did, and how fo you cope with the not knowing?