It could be from any number of things...most of them not serious and/or easily correctable. However, could there be a chance you are pregnant right now? If not, perhaps you are having early menopausal symtoms. I started going through it at 45 and had severe mood swings and hot flashes until my doctor got me on hormones. But no matter what it is, it doesn't do you any good to avoid seeing your doctor because of fear. If it's serious, then you will only be harming yourself by avoiding your doctor.