Is It Normal To Have Irregular Periods After Coming Off Yasmin?

hi i stopped taking my Yasmin pill in august 2010 and started ttc and had my last period after the pill on the 21st august and came off on the 25th after that i didn t have a period until 5th feb but only until the 6th then again on 5th march until the 8th then non until the 15th may to the 20th. Is it normal to start and stop periods after coming off the pill? also, how long until i should go to see my doctor because it seems to be taking so long to concive is this normal ?