Not sure what to do

I have been trying for a baby for a few years now I am 5 days late my periods which isn’t normal I am normally bang on every month my last period was the end of January and it lasted one day and was very very light then it was tiny bits I took a test when I was three days late but it said negative am I to early to be testing I just can’t stop thinking about it and now thinking is it me thinking about it that’s making it late?