I have T.N. like Koala ...T.N dose not always start as a pain and many times even after one is rx with T.N. one of the things they feel is a tugging feeling which is diffrent then the firey or zapping pain.T.N has many symptoms as I talk with many many people like myself who have diffrent types of t.n. Some have a feeling of crawling or throbing . Some its a pinching feeling .or a heavyness like presure.
I am hoping it is just a muscle and nothing seriuos. You should keep note of when it happens ,what your doing at the time ..bending over changes the blood flow in the head and that may be why you notice it then. make note of it and any other time when you get the feeling. then tell your doc.they will know better then anyone what it may be. and I pray it is noting at all.
PEACE
BMW