Why does it hurt all of a sudden in and around my belly button? could it be from lack of exercising from working from home or can it be ibs or gastritis?

Many gastrointestinal problems may cause mid-abdomen pain, i.e. around the navel area (belly button) but lack of exercise is less likely the cause unless you had been sedentary but suddenly you works your abdominal muscles a lot in the previous 12-24 hours. Pay attention to the other associated symptoms such as nausea/vomiting, gas, constipation or loose bowel, only worry if pain persists.