It can, I would also take a pregnancy test to be sure you took it before you started ovulating.
This is why I always recommend to read the little pamphlet that comes in the Plan B. I’ve taken Plan B twice and it says that it can make your period late but if you do not have a period within so long to take a pregnancy test because Plan B is not 100% guarantee you won’t get pregnant
I’m pretty sure it delays ovulation. So it is generally only effective if you haven’t ovulated yet when you take it. In saying that I think it can definitely cause some irregularities in your coming cycle after taking it.