I had unprotected sex on April 21 my boyfriend of 4 years thought he had came inside so I took a plan b 3 hours after sex. However I did not have an side effects of any kind which I read that can happen to some people. Well I am now a week late on my period which was suppose to start May 9 and I have been experiencing some bloating, heartburn, nausea, cramps extremely sore breast & headaches. I have taken a test but it comes out negative & im starting to freak out.