You might want to consider asking your neurologist to check you for Hashimoto's Encephalopathy, which can cause bad migraines and one-sided paralysis. Most patients who have HE have NORMAL thyroid HORMONE levels- but highly elevated thyroid ANTIBODIES (which typically are not checked UNLESS your thyroid hormone levels are off first).
This is a new disease and so your neuro may not know about it yet.
Good Luck!