Welcome, and I hope we can help. Kathy gave you some great advice and I will elaborate on some of it. First, you are truly not getting from the doctors what you need. You are clearly going to have to solve some of the problems yourself. One of the things we do here is to help people advocate for themselves more effectively.
You really do need to collect ALL of your medical records so that you have copies. This includes results of the testing you have had. Then when a doc doesn't have the records he needs you can provide it for his office to make copies then and there.
It would be a good idea to make a timeline of how and when your different symptoms began and how long they stayed, went away (if they did) and returned. That will give the docs a better idea if you are truly having relapses and remissions. We have a little article on making a timeline. It might help.
http://www.medhelp.org/health_pages/Multiple%20Sclerosis/The-Importance-of-the-Timeline/show/765?cid=36
I can see why you are writing on an MS Forum. With two siblings with MS, it is certainly on your mind and your are at a fairly high risk for it. You are also in the age group that it begins most commonly. Your symptoms of numbness and tremors, plus the great fatigue are very suggestive of MS, but not very specific to it. There are many mimics of MS and you should have already been tested for them.
The MS Specialist was basically trying to tell you that all of your symptoms were anxiety related - perhaps because of the MS in the family. Shame on him! BTW - is anxiety a problem of yours? If it is, it is a good idea to address it through treatment, so you can tell the next docs - "No, this isn't anxiety."
You say that the numbness you have moves around. How quickly does it move around? How long does it last? What is your neuro exam like? Do you have any weakness other than the severe fatigue? Have your doctors looked at other things like your thyroid and blood counts? Have they checked for for other autoimmune diseases?
Your doctors should be far more concerned that you have a growing number of lesions in your brain. Could you give us the results of the last brain MRI you had? Not all lesions point to MS, but with your family history I would certainly be suspicious.
Your spinal LP was normal. I would only accept this result if it was done on a high-resolution MRI. Your LP was also normal. This does NOT rule out MS.
Tell us about the tremors. Are they worse when you are quiet and not moving or do they appear when you move?
Now, the gunk you spit up out of your throat is nasty and would have nothing to do with MS. It sounds like you might indeed have sinus issues, possibly sinusitis with post-nasal drip. The ideal way to look for sinus disease is by having a CT scan of the sinuses without using contrast. I would hope the ENT would have considered that.
Finally, do not ever let a doctor tell you "there is nothing wrong," because they didn't find anything. You KNOW something is wrong, they just couldn't find out what.
We'll be waiting for the answers to these questions and I hope you stay.
Quix