Thanks for using Healthcaremagic,
You had unprotected sex yesterday and took emergency contraceptive pill
immediately; these pills have very good protection against unwanted pregnancy
You must understand pregnancy depend on exposure during ovulation which occurs 14 days before the expected date.
As you have already taken Pill there is very less chance so you should wait for your period or sometime you may get withdrawal bleeding.
If your period get delayed then test for pregnancy in urine and if it is negative then wait for period as it can get delayed.
If positive (Less likely) you have to visit a Gynecologist for help.
In future practice safe sex
as it protects from both unwanted pregnancy and sexually transmitted diseases.
Hope this information helps you.
Dr. Akhilesh Dubey M.D.