Ive been on the pill for over 6 months but think it might have failed?

ive put on a bit of weight but thought it might be contentment with my fiance. my have also grown and ive been really tired all the time. my period came early this month and lasted longer than the sugar pills. for the past few days ive been super hungry and have naseua sometimes.could i be pregnant or just a lot of coincidences?