What Causes Constant Upper Back And Neck Pain, The Hard, Painful Lump On My Right Shoulder, And The Pressure Above My Right Ear And Jaw?

Hi, I have upper back/neck pain from a long period of poor posture sitting down. Over the last two months the pain is now constant in the right side of my neck down right shoulder into my right arm. There is also a penny sized lump on my right shoulder (i believe by upper right part of scapula) that is hard and painful to the touch. I don’t necessarily have headaches but this constant weird pressure feeling above my right ear and right side of jaw.