Can dissociating cause someone to feel more stress? if someones feelings and reality are disconnected, can that cause them to physically feel bad and stressed?

Anxiety will rear its head whenever we feel a loss of control or self-determination and the sense that we are adrift and manipulated by outside forces. Unopposed fear is stressful. At 20 years old, you must take on responsibilities that used to be handled by others, and by disconnecting, you feel better. Anxiety motivates you to reconnect and act. Stress is anxiety not acted upon, so react.

It is not feasible to provide an opinion without additional history; physical examination may be some tests. It would be prudent to see your doctor to see if you may be depressed. Depression is treatable. Counter-intuitive as it may seem, exercise may help. Start with low intensity exercise such as walking and gradually increase the intensity as tolerated. Drink more water. Wish you good health!