EC after 16hrs

Mariah • 24 P.R.P 04/15/21💖🎀 A.J.P 01/30/24<3

So my s/o were doing the deed and he pulled out and went to go back in and the condom broke. He wasnt inside but i took a plan b about 16hrs after it happened. How effective will it be. Also im like 3 days away from starting my ovulation cycle. My period just ended yesterday.