I hate to break it to you but that work table of yours that you spend hours on is actually killing you. Those countless hours that you spend at the table, motionless staring at the screen in the name of productivity is affecting your body and not in a good way.
You can't deny that pain you feel in your neck, the pain in your back, and even that confusion in your brain. Instead of remaining glued to that table all day, stand up, stretch, walk.
Everyday you sit at work from 9 to 5. You sit when you're eating. You sit when you're watching TV, you sit when you're taking a break, and you're not even 70 yet, but yet, your joints are hurting already.
Here's what sitting all day does; it weakens your muscle, affects your heart, makes you gain weight faster. Your body was not meant to be in one place, it needs to move. So like I said earlier, stand up, stretch, move, walk around, don't allow your chair and your table to actually short your life span.