Spotting

Raven
I started spotting 5 days before af due, and it lasted for 4 days. First 2 days it was light and pink and the laat 2 days it was a bit more than the size of a quater, and brown. Now I'm two days late(af was due yesterday/Friday). I took a first response gold test on Monday and it said negative and so did a urine test at my doctor Tuesday. Since I very first gor my period it has been regular. Is there a possibility the tests were too early or is it more likely my period is just wacked up?