I had unprotected sex on the 21 of august I have been gagging a lot and ceartain smells make me sick and it the the first day of September but also I took a pregnancy test Tuesday the 29th and it said I wasn't pregnant some one told me I took it too early so now that I am feeling the Symptoms I'm feeling now could I be pregnant iwas fertile the day before I had sex and I was ovulating the 19th of August my cycle lasts 28 days and my last period started on the 6th of august please help