You may feel a slight stretch but they should be comfortable. If not, check with your doctor. Sitting problems are becoming more apparent with the age of computers. However, problems have existed long before this. People often experience soreness or stiffness in their necks, backs, shoulders, between their shoulder blades, and even into their wrists and hands.
Headaches are another common complaint.
Your position is a key factor in management of these problems at work and at home. It is also important to avoid a head down position for any length of time as this leads to straining the back of the neck. Try putting your work on a reclining surface. A good lower back support is important to you to lean against. Many people feel more comfortable with a small folded towel in the small of their back.