Trigger points are painful nodules that defy a normal description of their source. At one time. it was thought that a trigger point is the insertion point of the motor nerve into the muscle belly but prior studies have not held that theory up. As a chiropractor, I had found many trigger points that responded to deep tissue manipulation and as a surgeon, I have injected many with some good results.
I personally think that trigger points are as a result of some pathology (degenerative disc or facet or nerve root compression) but after a period of time, can be self-sustaining foci of pain that need to be dealt with separately. Dry needling or acupuncture can be helpful and if nothing is successful, an injection of a small amount of steroid with lidocaine can be helpful. Be careful with the location in the neck as some less than fully meticulous therapist might put a needle in the wrong area and cause some damage.
Trigger points are not typical pain generators by themselves. You might want another very skilled injectionist to look at the source of your neck pain.