I Had Sex With My Wife Without Using Condom. I

I had sex with my wife without using condom. I withdraw my penis before the spam came out. But, not 100% sure whether anything was left inside or not. Thus, my wife is planning to take i-pill (emergency contraceptive pill). At the same time, we are worried that if no spam is left inside then taking i-pill will be a wise decision or not? We do have the plan of taking our 2nd baby after one year not right now. Thus, considering the situation will you please advise me? Thank You