3 week headache

I have had a headache for the past 3 weeks.  Initially when it started, my left arm went numb and my fingertips on that arm turned really cold.  I left work and went to my primary care provider, who thought I was having a migraine with "neurological involvement?"  I left the office with yet another prescription for Zomig, which I took and the headache seemed to go away.  It returned the next day...took Zomig  and on and on since then.  Last Wednesday, I had what I have called the worst headache ever.  I thought maybe I had yet another sinus infection so went to the ENT who concurred and thought maybe the sinus stuff was triggering the headache.  So he sent me directly to the Neurologist, who game me IV Imitrex and solumedrol.  Headache again eased up.  The next morning I woke to find that I was dragging my left leg.  Called Neuro, who ordered a CT without contrast.  CT was normal except for an 8mm meningioma anterior falx.  Neuro is not concerned about this finding and doesn't think thats the cause of the headaches.  Now, I am extremely dizzy (I feel like I am on a boat just floating) particularly when I make any sudden movements.  Also, when I cough, I have the most excruciating pain in the back right of my head.  Neuro is attempting to order an MRI with contrast which my insurance company is denying.  I am frustrated because I am not sure what's going on and my quality of life has been dramatically impacted.  Can you offer any suggestions as to what else I should request?  Oh yeas, Neuro is calling this a compilcated migraine.  And I have gained 10 pounds since this all began.  Cardiologist thinks thats because of the steroids and water gain as my legs were really swollen on Thursday - last day of the medrol pack.  I also take atenolol 50mg per day for Mitral valve prolapse with mild regurgitation (been taking this for about 5 years).  Resting heartrate without is is between 104-120 and was as high as 144 before meds.