sharp pains in my head

I am at the end of my tether because every so often (about twice a year) I get sharp pains in my head - on the left hand side - I feel as though I have brain fog and my head feels as though it jolts & I feel off balance and off colour. I can feel like this for more than a month. I have had two MRI scans and both came back clear (one in 2011 and the other in 2015). I often wake in the middle of the night and sometimes I have sudden almost panic attacks and my heart rate seems to increase. I often feel that my body is running really fast and I am out of sync. Sometimes my ears seem to be 'tickly' or they feel full and on occasions I have pains in them. I am in despair because I don't know what is wrong (nor do the docs) and I was wondering if it could be something to do with my thyroid? Should I go for a test? Does anyone else have these symptoms. I am 61 and I am not on medication.