Suggest Solution For Irregular Periods, Brown And Foul Smelling Discharge

hi, i am 30 years old,have a baby 1 and a half year old.my cycle were regular but from last 4 -5 cycles it became irregular and from last cycle i am having chocolate coloured discharge instead of blood and its foul smelling.sometime it totally stops and then again starts.its happening for last 20 days.i hqave no other problem such as difficulty in intercourse,or any pain or bleeding.what should i do?