Hello, and welcome to the site
As you’re a medical student, I recommend that you read Polman et al (2011); this sets out the latest diagnostic criteria for MS. The NICE guidelines are mammoth and currently under revision, but they are worth a look at too (google “NICE CG8 full guidelines for MS”).
As you know, it’s very possible that the lesions are due to migraine, but if they aren’t and the neuro reckons MS is more likely, things could take a few different routes depending on the number and location of the lesions and the pattern of your symptoms. It’s quite likely that the neuro will send you for an LP and possibly EPs before coming to any conclusions though.
The thing to expect is that diagnosis will be slow. If it isn’t, then it’s a bonus!
If you get a diagnosis of MS, then you should also get assigned an MS nurse. She/he will be your day to day point of contact. GPs are usually pretty hopeless at dealing with neurological conditions, so you really have to take control of your own symptomatic treatment: if you need meds for a symptom, you usually have to call the MS nurse and get a recommendation / approval for what you want, then contact the GP to actually get the prescription. Same goes for physio etc. Everything goes through the MS nurse (unless it’s something that the GP can do without approval). The nurse can contact the neuro to check things out as necessary too. How often you see the neuro depends on how active your MS is, whether or not you’re doing a trial and what kind of MS you have. It usually varies from quarterly to annually (but some people don’t bother).
If you are diagnosed with RRMS and you meet the NICE criteria for disease modifying drugs (DMDs), you will have the option of four injectable first-line drugs (Copaxone, Avonex, Rebif, Betaferon). If your neuro thinks your MS is highly active / aggressive, you might be offered Tysabri. As you know, there is no cure for MS, but DMDs do reduce the frequency of relapses and help with progression. They also reduce the severity of any relapses that still occur. Actually getting hold of DMDs can take a while: a fair amount of paperwork needs to be done (including approval from the PCT) so it generally takes a while. If you think you might have RRMS, you could always pick one before you go - telling the neuro which one you want straightaway might save you several months(!). Check out the msdecisions website for info on DMDs.
If you are diagnosed with PPMS then I’m afraid you will be pretty much on your own - there is no DMD for PPMS. Saying that, there are trials going on at the moment for PPMS and I think some are still recruiting. (Have a look at http://multiple-sclerosis-research.blogspot.com/) You should also have a look at ldnresearchtrust - LDN is definitely worth a try if you have PPMS.
One thing to do before you see the neuro is to look back over your medical history to try to remember any other potentially related episodes. It’s important info.
Hth! And good luck!