So I have had my period 4 two days and its so light that I have gone through one pad a day its dark brown on the pad and light brown when wiping, is this normal or is it implantation bleeding when can I take a test?

It can be normal, the color varies from brown to deep red. Everybody is different. Are you on any kind of birth control? That makes periods light. You can take a pregnancy test now if that is what you are talking about-first day of your "missed" period... or light period, in this case.