6 years is a long time to carry a grudge against a doctor.
MS, and a ton of other neurological problems, take a long time to diagnose. If all of your tests came back "negative" 6 years ago -- all that indicated was that whatever was ailing you then, and apparently now, wasn't significant enough to show up on MRI's. You didn't mention if you had a spinal tap then -- it might have shown something that the MRI missed.
At any rate, you clearly need to see a neuro. And now is a good time to do that, with so many different symptoms going on. You should sit down and carefully note when symptoms started, when they seemed to go away, and when they've come back. Do it as simply and plainly as possible, then go to the neuor that your doctor referred you to, try to remain calm and matter-of-fact. Say something like:
I was here 6 years ago, you told me I was suffering from depression. However now it is six years later, I have many more symptoms, and I would like to be tested to find out what is going on with my body. Here are my symptoms and when they occurred, and what is going on now: (and list your current symptoms, starting with the most troublesome and working your way back to the "minor annoyances", if any.)
Then be prepared to undergo testing again. A 6 year old MRI is way outdated. A new one may show something. Ask about "evoked potentials", and blood work to rule out other things (there is no blood test that will diagnose MS).
(And it's helpful for us with vision problems if you do like I did with this response -- type just a few lines, then a space or two, then continue with a few more lines. It's much easier to read. Thanks!)
...I am not a doctor, nor health professional, and don't pretend to be one, here.....