Is this really a migraine? Starting to panic – please help

Background:   54-year-old female going through menopause.   No real period since last Apr, had hot flashes very badly May and Jun but now gone.   Long history of allergies and been on Flonase for years.     Current:   I went off Flonase a week ago Sat (just wanted to get off medication).   Last Wed, while driving, I had a dizzy spell (not spinning feeling, just slight dizziness and sense of unreality).   Then headache started between right eye and top of head on right side.   Sun glaring between clouds really intensified the unwell feeling. I was also slightly nauseous.   When I got home, I felt totally exhausted – went to bed and slept 12 hours.   Saw PCP the next day.   He did neurological reaction tests which were normal.   He said it sounded like a migraine but is sending me for an MRI to set my mind at rest.   (I tend to have Health Anxiety – never make up symptoms, but when I have them I panic and think the worst).   Fri (2 days after the episode), I started what I assume is a very light period – first since Apr.     I am still having pain off and on but it’s not severe.   I feel stuffy in the head and in the ears (when I eat, I hear myself chewing more than usual if you know what I mean).   I have also been having a grinding noise in my spine at the base of my skull when I turn my head and some pain/stiffness radiating into shoulders.   Could this be a migraine set off by fluctuating hormones?   Could going off the Flonase cause any of these symptoms?   The MRI is Wed, but I’m really getting panicked that I have something serious.   Any ideas?     Any advice (or reassuring words) would be greatly appreciated!  Pam

I'm hoping you all are not thinking I have the classic symptoms of a brain tumour and are afraid to say so.  I've forced myself not to google, but I'm really freaking here.  Anyone have any good (non-tumour) ideas?  Thanks.