I only crave fast food :((((

Everything makes me feel nauseous except fast food. I crave the hell out of potatoes and French fries at all times. I absolutely cannot eat in the mornings and I get sick if I do. Even my prenatal vitamins make me gag. Around noon it hits me that I'm hungry and I begin to feel as if I haven't eaten ever in life and I almost faint.
Any tips on how to deal with my weird nausea? I'm 5 weeks btw.