I don't know what's wrong with me. For the past two or three days I have been feeling terrible. I'm really lightheaded, and it's getting worse. Every time I move my head I feel like all the blood rushes out of my head and it's difficult to see. And I have this headache that comes and goes. And sometimes I feel really nauseous, but i can't throw up. I've been eating a little less since i began feeling sick, only because i start to feel sick after eating for a minute. And I am extremely fatigued. I get tired just from walking up the driveway, which is extremely out of the ordinary since i'm an athlete. And just today I've started to experience some extreme mood swings. I was watching television and I randomly burst into tears and was crying uncontrollably for no reason. What's wrong with me?? I don't like going to the doctor unless I absolutely have to.. I really need some advice. BTW I'm a girl, 17 years old. And I don't think I'm pregnant because I only just had sex for the first time a week ago and used protection.