Advice!

I just took a pregnancy test and it came out negative on 3/27/16 and my expected period is supposed to come tomorrow 3/28/16 according to Glow but it usually comes on the 1st of every month and usually right on time. 4/1/16 
My husband and I do not use protection of any sort besides the withdrawal method. Should I wait to see if I miss this period to take another test? Or is this the correct result? What are your thoughts?