I'll will second that.
It could be referral or protection or balancing.....
As a bodyworker who works on organs all day long: visceral manipulation--the work of a French Osteopath named Jean-Pierre Barral, in case you are interested. I see this kind of thing all the time and have my own experiences. Just two weeks ago I took too much SSKI
and my kidney/adrenals got really unhappy and my back locked up and got really sore.
when organs are unhappy, under strain, vertebraes on the same nerve line will often lock up and then their local musculature will go into contracture and eventually start to hurt. Sometimes it is done for protection and other times balancing. other times it is a chain of events that isn't really clear
I had a client with severe elbow pain a couple of years ago have total relief when I freed up the adhesions around her uterus from two C-sections. Her brachial nerves got pinched by her scalene muscles and her first rib. This area freed up instantly when I released her uterus. It appeared her body was trying to balance the lower strain by creating an upper strain. the body has to keep balance to some degree else things get worse
so maybe your body is trying to pull you into a forward bend to create slack in the abdominal tissues to created some ease for the duodenum and however it is doing it is creating pain in your neck
maybe it is some kind of direct referral.....
hope it gets better for you soon!