Chronic Migraines treated by Percocet

I have had chronic migraines for a long period of time have done all treatments you could even imagine. I weened myself off with a doctor that would help me. So far 15 days without Percocet and no desire to use them again. Also had been to a inpatient hospital for 2 weeks with no avail. My withdrawals are extreme migraines everyday in the morning then in and out all day, along with nauseous, feel spacey, Changes in my tolerance to cold or hot. Irritated insomnia decrease in appetite. Worse is the daily pain when I awake and cannot take anything. Is this normal? How long can this last!