Am I doing something wrong?!

My period is usually very normal. I can pin point the day I start my cycle. But this month I'm about four days late so im sure you can understand how excited I was. Until I took a pregnancy test yesterday and still got that heartbreaking negative result. Idk if im testing too early or if maybe I'm just late. I mean there are no other symptoms besides a late period. Idk what I'm doing wrong.