Most of my CTAs were taken at ER. Including the positional one. When I went to ER that time, I told the ER doc that I felt like passing out when I rotate my neck, and please can I get a CTA in that position. A bit forth and back and they did it.
Whooshing sound is said to often be pulsation in the IJVs, which may be true may be not. Mine has been gone after the bilateral styloidectomy. I had one IJV completely compressed since 2020 and the other compressed maybe 50-75%.
Tight shoulder muscles might be a sign of weak rotator cuff muscles, stiff biceps/triceps and especially deltoids. Also weak back muscles. If you have a chance, get a professional massage on arms and shoulders (but not on the neck) and see if it helps.
You can check some muscle diagrams in some of my self-physiotherapy-advocating posts . Long story short, weak postural muscles (long decades at the computer leaning forward, and one arm extended further than the other to hold the mouse?) force “power” muscles into spasms in order to hold the body in shape and prevent from collapsing into a pile. Neck is full of strong muscles, and some of them may literally pull the head back too much.