What Causes Headaches,tiredness,heartburn And Cramps?

I've been having headaches and aleve doesn't help.. I'm so tired I end up having a three hour nap everyother day. I've been getting heartburn randomly at night and feeling nausea in the mrning along with my breast being tender.. I don't feel bloated and I'm not craving weird food..I've been having cramps in my legs and sore feet.. Could I be pregnant??