Thank you for your question and welcome to EmpowHer! It is likely that you are experiencing breakthrough bleeding, which is a normal side effect of oral contraceptives. Breakthrough bleeding is lighter than your normal menstrual cycle. If the bleeding is heavy, or lasts a long time, you should consult your doctor.
Cyestra 35 instructions for usage specify that you should continue taking the medication through spotting or breakthrough bleeding, even if you have missed a dose. The only time it specifies to discontinue use is if you miss a period (which can indicate a possible pregnancy).
If you are unsure of how to resume using the pill, your medication should always include an insert with instructions. Otherwise, your doctor or their nursing staff can give you clear instructions.
I hope that helps! Let us know if you have any more questions.