Diabetic, On Insulin, Get Headaches Starting From Neck Through Ear And Into Temples. Cause?

hi i am at a loss and feel like just giving up here, im a 38 female , 300 ilbs and i have diabetes type 2 on insuline, for some time way to long now i have been dealing with headaches . mostly starting from the kneck and up thru my ears the into the temples. i feel as if my kneck is stiff and my head is numb and painful to no end. was put on gabapentin up to 3 xs a day and it makes me like a zombie, i also take amitriptylin at night 3 of then and im on lithium 1500 a day 3 - 300 at night and 2 inthe am . i cant find a relief and the doc cant see me right away , im begging for help im a single mom and cant take not being able to function.