It goes away after some rest, or a night's sleep. It's tempting to think that means the problem has gone away. But keep in mind that the pain is really the result of years of accumulated stress, and that you're hovering just below the pain line. Serious problems come when someone in this state starts working long hours to meet some deadline crunch. Soon, the level may never go back down below the pain line.
Constant pain can result.
Desk jobs are characterized as physically easy. But the human body evolved to be in motion, and remaining static while performing micromotor motions puts a huge strain on it. You're a computer athlete. And like other athletes, you need to be concerned with nutrition, warming up, stretching, cross training, and rest, if you want to avoid injury. Muscles in motion contract and relax.