I guess a welcome is in order, but don't be too sad yet.
First off, it's still only possible according to your post. So it could be a variety of other things, and I know the anxiety of it all can be overwhelming. I think it's fair to say that we all wanted to know what was wrong, yet didn't want it to be something awful.
I remember telling my wife, gf at the time, that I wished it was MS because then we would at least know what it was. This was when I was in a Russian Hospital (and it wasn't a lot of fun) for 12 days and had daily blood draws, IV's, and injections into my eye (even with anesthesia it still hurt like hell). I was in there for Optic Neuritis. Before i even got to the hospital I had been told it was an infarction, a brain hemorrhage, I had had a stroke, I drank bad alcohol, I was doing drugs and wasn't telling the drs, so I was scared shitless. To be told 4 different times I was dying, with 4 different diagnosis, was WAY overwhelming. So I understand the anxiety, and I'm sorry that you have to go through that. This all led to me having a 3 inch needle injected into my eye socket (yep, through the eyelid and out the back of the eye) at 2am without anesthesia because the dr wanted to go home. After all of that, settling for MS was doable, because it wasn't a death sentence. It isn't. Think of it like a severe handicap, like in a golf game, because you are way too good at life.
There are a ton of medications for MS, and it isn't something that the medical community glosses over. Treatment is improving, and that's great. There are new focuses on what causes it and how to treat it, and there are hundreds of ways to manage it and still have a full life. Maybe you got me on a good day today, but it really is not a death sentence. To be fair it is very difficult to cope with the initial news, and I'm not trying to be dismissive in that way. I remember shutting myself off from the world for a good 3 months, and not doing anything for the next 6 months, and I just had to learn to accept that MS was what I had been dealt. It really isn't a death sentence, and I know that now it may feel like your world is being stripped of everything that had been promised, but it's really not.
I was 26 when I was diagnosed with it. I was living in Russia with the love of my life, now my wife, and I was pissed off at the world. I felt like everything that anyone had ever promised me was being ripped away from me. Like I was suddenly going to be crippled and unable to do things for myself. I remember feeling embarrassed, broken, violated, ashamed, and angry. I didn't know what to think or how to act, and I remember it was probably the darkest time in my life. I knew that my mind wasn't broken, just that my immune system liked to be over aggressive. The one thing I asked my wife, was to never treat me like I am broken. I couldn't deal with that from her, because I wasn't broken. I also asked her to not always ask me how I feel. Now if I tell her I feel dizzy, or my hand is tingling, then of course feel free to follow up the question, but I don't need it everyday. I want to give my MS as little recognition as I can. It isn't what is defining about me. There are many other things that define me, and who I am, and I refuse to let MS be one of them.
Now I mentioned that after being diagnosed I went into a spiral of not knowing what to do. I really didn't. Somewhere around Christmas in 2013, I finally got out of this funk. It took sometime, and I just told everyone to give me space. By this time, I had left Russia, with my wife still there, living with her family, and I was back in the US with mine. So my support system, was gone, which didn't help. It really didn't. But somewhere around christmas I finally got over the fact that yes, I had MS. Between being diagnosed and when I came out of the funk, nothing had really changed. I started taking my meds, which helped my systems clear up (bending you head and feeling all the muscles in your left arm twinge like you hit your funny bone really sucks). It was then that I decided to get my life back on track, and that sounds easier than it actually was. What nobody told me, was that I would now have to plan every last detail. I wanted to return to Russia to be with my wife, again gf at the time, and in order to do so I now had to worry about customs and medications, and creating a reliable supply chain. I had to detail everything.
The organization that i have learned from this has been wonderful. It has also given me a reason to start getting into better shape. Yes, I still hate exercising, but eating and drinking healthier foods, and really being concious of my weight are things that I was passive about before. Now, I feel much better most days, and I'm more confident with myself. This isn't to say that my MS is gone completely. It has taken more of a "back-seat driver" position in my. It's very content with everything that I have done, but every now and then it will let me know via fatigue, dizziness, odd sensations, or just pain (I had some nerve damage before MS, and now it loves to twinge those spots), and when it pops up I know that I need to rest.
I really wish you the best, and I hope that it is something that isn't terrible. I hope it is something super fixable, and won't need to be managed on a daily basis.