Swirling Sensation Near Temples At Night. Normal Blood Test. What Is This?

Hi there, probably an unusual system and quite challenging to describe, but I keep getting a swirling sensation around both sides of my head near my temples, I often try to rub it in order for it to stop. I notice it mainly at night and when I go to bed. I recently had a blood test done for everything, heart monitors test and other than a subclinical hypothyrodiasm (which I kind of new already) everything seemed fine. I have also had an eye test and that was all fine. I haven t yet had an MRI . What could this be symptomatic off? I am gettng a bit absent minded as well and very tired alot of the time but that I think is due to the thyroid issue. Could it be a tumor? But I don t really get headaches . many thanks