Why ??

So I last had my periods may 29th lasted 5 days normal for me . the app says I was due JUly 6th for my period I didn't have my period yet not taking any birth control I had a pregnecy test on the 5th of of July at the E.R due to I was throwing up everywere came out negative I have sex with my fiance every day almost . is this pregnecy systptoms