Hi I Had My Period (withdrawal Bleed Two Weeks Ago)

Hi I had my period (withdrawal bleed two weeks ago) which was normal however yesterday I had very dark clumpy discharge and today along with very light red blood only a small amount. I am on microlite pill for the last 6 months however I missed two pills this month in which I had to take two the next day on two different occasions could this be the reason for my break through bleed