I am also experiencing similar pain. I am 19 weeks pregnant and my belly button and the area right around my belly button hurt from time to time. It is sometimes constant but other days doesn't hurt much at all. I have been experiencing this for a couple weeks now.
The immune system is intricately connected to the hormonal system and the brain via messenger molecules, so that emotional stress and factors like insomnia have a great influence on its ability to function properly.
Sleep duration is related to length of life, with a greater risk of death in those sleeping fewer than 6 hours a night. Sleep deprivation is also linked to vehicle crashes and deaths. Insomnia early in adult life is a risk factor for the development of clinical depression and mental health disorders.