Headaches.nausea.sleepy.no energy.eating a lot gained a lot of weight...spoting around menstral time but not normal...what can this mean?

Duration?: If the headaches and nausea are new in onset... I'd be concerned about a process involving the brain. Combined with the symptoms of lack of energy/weight gain, etc. I'd be concerned about a possible pituitary process. If the headaches are long-standing with nausea - this could be migraine - but with the other symptoms i would consider a hormonal (thyroid issue).

May be >1 thing: That's a lot of symptoms to try to explain with one condition or process. You should arrange to see your doctor for evaluation of these symptoms. In the meantime, cutting way back on your eating, particularly cutting down on carbs, should help reduce the weight gain, and might help with some of the other symptoms as well.