Hi Anonymous and thanks for sharing your concerns with EmpowHER.
Emergency contraceptive pills are meant to be taken after having unprotected intercourse. They reduce the chance of pregnancy by about 89% when taken correctly, it is not clear what, if any impact, they have when they are not taken correctly. Yes, you could get pregnant.
Your period may be late for a number of reasons, including stress, which impacts your hormone levels. Taking an emergency contraceptive also impacts your hormone levels.
The only thing you can do at this point is to wait things out. You are not going to be able to force your period to come. You can take a pregnancy test 14-21 days after having unprotected intercourse to determine if you are pregnant.
Hope that helps,