3 month old boy and spotting

So me and my partner have a 3 month old boy I'm on the pill take it every night at same time 7.30pm but I had slight spotting at begging of week but nothing came of it was due on 25th december (been 33days since last period) cant someone tell me if I should do a test as I didnt get any of this with my boy only symptom I had with him was I felt sick on the way back from france and didnt test till after daughters birthday