Some of your itching might be dehydration and dry indoor air. Have you tried running a humidifier and increasing your water intake?
Your fear, if not controlled will bring the pity party invites to your door. Please do not answer and tell the pity party invites that you will be refusing them entry into your life.
Though you do not yet have a definitive diagnosis, if you attack your current problem using the hypothesis of MS, maybe you can obtain a degree of control and sanity.
On those occasions when you are tired, you need to just nap. It is no use fighting and resisting what your body needs. Climb in bed with your book, keyboard, remote control, knitting, or whatever and just hibernate for a week or so. Afterward you can read through your journal and try to determine what might have triggered your problems.
Leave plenty of time to just 'veg-out' in front of the TV. Your brain can use the rest.
My worst vertigo happened while I was lying down. I thought I was going to spin right out of bed. When I felt like I was turning clockwise, I rolled my eyes counter-clockwise. Once my dizziness switched to counter-clockwise, I rolled my eyes clockwise. This worked for me. It did wear me out and I was soon fast asleep and no longer fripping the sides of my mattress.
I have found that for me, lying while propped up at a 30-45 degree angle has allowed me to get the best rest (and helped eliminate my choking sensation).
Try different things until you discover what works for you. Eventually, when you discover what works for you- BAM- you have your DUH moment. Remember you are uniquely created and as such, what works for you may be unique too.
Have no fear!!