Why Had My Bleeding Persisted For 10 Days After Taking Primolut N?

Hi, would I still bleed after taking 10 tablets of primolut N if I was pregnant & didn't know. I finished primolut last Wednesday & had 2 days of spotting & 2 days of a very light period. Iv used primolut in the past & always had a normal flow after taking it. Thanx so much