I have been on birth control for about 3 years and my period is anywhere from 3-4 days in length. Most of the time, it slows after 1 active pill and then stops after 2 active pills. This month and about 3 months ago, I noticed that my period stopped for a day and then I had pale brown discharge with a little blood the following day. I had a normal period that started about 5 days ago. I noticed having a little spotting today, after not having much bleeding yesterday. Is this normal? Could I have endemetrosis or another serious issue?