Hi Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concern.
Stomach pain & bloating are common side effects related to intake of postinor 2. These symptoms would last for 1-2 days. You could take painkiller like ibuprofen/
acetaminophen for it. These are not be related to pregnancy.
First of all having a period after sex means you are not pregnant, however the flow should be heavy as normal. If you had normal period after having intercourse then, intake of
emergency contraceptive pill like postinor was not necessary.
Emergency contraceptive pill or I pill work by preventing
implantation of fertilized egg on uterus. As you have taken the pill 42 hours of sex, You should now relax as pregnancy possibility is very less.
Use condom or regular contraceptive pill as method of conception in future. Taking more emergency contraceptive pills can cause problems like
irregular periods, ovarian hyper-stimulation syndrome & even
infertility.
If problem persists consult a gynaecologist
Hope this information helps