Spotting after using contraceptive pills

Hi.. I used to get regular periods before I consulted a doctor for pregnancy plan.After my first consulting with doctor, I undergone scanning and found that I had harmonal imbalance and PCOD. Doctor told me to use METITAL tablet and contraceptive pills "CARPELA" from the 5th day after my period  for 21 days and she also told me that after 21 days on stopping these contraceptive I will immediately get periods again, now after using those tablet's I had only spotting (not bleeding) during my period. After that my doc suggested to use a bit high dosage contraceptive "OVRAL". Could you help me with my situation. Is it ok to use high dose contraceptive for second month also?   suggest me what to do next. Should I continue using "Ovral". Or should I do ultrasonic testing..