Hallow Dear, You have taken Plan B pill within 72 hours after the unprotected sex. These are very effective pills to prevent the pregnancy when taken within 72 hours of the unprotected sex. These pills may delay the following menses by few days to a week. These pills contain progestational medicine. Progesterone is known to cause all the symptoms you have described. Some antacids like Pantoprazole will give you relief from these symptoms. If your menses are delayed for more than a week, you may opt for pregnancy test on overnight early morning first urine sample. Done earlier, these tests may report false negative results. I hope this clarifies your doubts. Dr. Nishikant Shrotri