Adding on a welcome to you. The doctor may suspect MS, and may be able to correlate a few things for the criteria based on initial suspicion, however much will need to be investigated in order to know if you truly have MS. In addition to the MRIs, a battery of labs should have been ordered as well.
I think you will find this write up informative because it speaks to what MS is, and what it is not.
As to meds to treat the disease. As mentioned above, the original traditional meds, Copaxone, Rebif, Avonex, Betaseron are not immune suppressants - they are immune modulators. However, when on an interferon, there is a potential to have changes in blood counts. So, you are monitored. Not copaxone - it's a peptide.
I have to make a correction here to what's been said in reference to your Mom - No one can know that it's possible your Mom has MS. Please know a numb foot does not rise to the level of concern for MS. Don't want you to worry :)
Also, the McDonald Criteria does not state that there has be a steady progression for dx.
If you would like to learn more about the dxing MS, and the criteria - our health pages are jammed with good information. You can find them toward the right of your screen.
Thanks for joining us again, and hope we can help.