Pregnant or stomach virus?

Lesley
So I was supposed to start this pat Sunday and nothing. I tested Monday morning and a BFN! It was a digital test. I'm super nauseas and have had diarrhea ALL day and I couldn't eat all day with out worrying I would vomit or poop. I took Femara starting Feb 10th ( it was days 5-9) and I'm scared to get excited only to be let down again. Could Femara delay my period? What do you think? You think it's a stomach virus or could I be pregnant?