What Causes Severe Fatigue, Drowsiness, Headaches And Tightness In Chest?

I am a 30 year old Female. I had a partial hyst in 2010 which removed my uterus. About a month ago I began to suffer everyday with burning painful nibbles. I am always every sleepy. I always feel very wore out. I have been keeping headaches . I have been suffering from tightness in my chest and my heartbeat will pulse high. I have lost a lot of weight. I often have to force myself to eat. I stay pretty nausea everyday. I am very nerves and don't know what is going on.