Am I pregnant ?

Okay I'm late on my period . My last period came about febuary 17 ... It's March 24th now ... I took a test a couple days ago and it came back negative ... My breast are not sore or tender my nipples are still pink how long should I wate to take another test ... I have all these menstral apps on my iPhone they all say I'm late one says I'm 8 days late one says I'm 6 days late and another says I'm four days late ... I have a First Response pregnancy test a early result one 6 days before your missed period ... I'm no nervous to take the test because I don't want to get disappointed by a negative reading ...