Upper shaft anchoring the hanger?

Is it normal for the upper shaft to be sore when you start a set? It always takes me about a minute into a set for this uncomfortable feeling in the uppershaft/head. My head doesn’t fill balloon with blood so I have my own theory for why I feel this soreness.

I think its because the tissues bunch up in the head/uppershaft and form an anchor, stopping the hanger. Therefore it is tissues in the uppershaft that are actually holding the weight on, while the tissues above the hanger and up to your body are enduring the stretch (assuming the hanger is on tight enough to grip them.)

Any thoughts on this?
P.S. I reached FSL 7” recently woohoo.