Hi, for the past week I have been having severe headaches, nausea, fatigue, tired, exhausted, weak, hungry and light headed. I don’t know what the cause is, I don’t believe im diabetic as last year I was tested and I was clear. I’m on an anti-depressant called pristiq which I have been on for almost 2 years. I’m only on 50mg so my doctor said to increase my dose but that hasn’t helped the symptoms go away, does anyone know what it could be? im worried that its serious and I have a brain tumor or that im dying.