Welcome KD. first, breathe. Just breathe. We often get so caught up in the anxiety of it all that we hold our breath, and starve our bodies of much needed O2.
I am sorry you have reason to search us out, but you picked a good crew. I am sure you will find more than one of us that has been exactly where you are. I was diagnosed without the Lumbar puncture or LP, but most folks here have had one. I am sure they will tell you all about it.
The first step is finding an MD that you can trust, and rely on to do right by you, and not just brush off your symptoms (sx) and concerns. Many of us have gone to the big city MS centers at least once while chasing the diagnosis (dx) of MS. There are more than 100 different diseases that can mimic MS including Lupus, Lyme, B12 deficiencies, Vit D def and so on. When the MDs look at someone struggling, they dont often grab a diagnosis and say "this is what it is" they often start playing the "this is what it is NOT" game. they will rule out the vitamin stuff, and lyme with blood tests. Same for Lupus, and other conditions. Once at the bottom of the barrel, they will be left with 10 or so to choose from, and then they start the "maybe its MS" dance. Be patient. Its rare for us to be diagnosed on the spot. Many of us went months and years before we received a firm dx.
Welcome to the club house. pull up a chair, and tell us your story.