Period late

Okay so my husband and I decide to have me go off birth control to help with our sex life. When on birth control I have no desire to have sex and can go a good 3 months without it and be fine. We aren't actively trying for a baby but we are not preventing it. The way we see it is no matter what we do God will give us another in his time not ours. Anyway I just finished the first month not on birth control. My period was supposed to start on Monday or Tuesday. Like it normally does (when on bc). I have been having a few cramps here and there. Sometimes when I wipe there is a faint brownish color. I took a pregancy test Tuesday after all cramps stopped and it said no. How long does it normally take to start after going off birth control pills?