See the pills you were taking were hormonal
pills,and you cannot play with the hormones and your body in such a manner,the period you got on second Jan would be due to hormonal imbalance and with that nothing can be predicted. So you might become pregnant also. Nothing cab be said now until you get your next period . And when you will get it can also not be predicted now. So wait till Feb 2nd and if you dont get it get a urine pregnancy
test done and a sonogrqphy done.