I've been taking birth control pills since August and they are the low estrogen pills. Since then I've gained weight and my period started out with a normal flow and color and for the last 3 months it's been lighter like it's almost not there and the color has been brown. I thought it was due to my yeast infection however I noticed that my last period was 3 days early and it was light like almost not there and it was a light brown. Is this normal? Am I over reacting? Do I need to take a pregnancy test? Help please