question: My periods are always quite regular , last month got the periods three days earlier that is on 4th Feb ,and later on march first had unprotected sex...took a pregnancy tests has periods were delayed , once or twice vomited , also had nausea feeling , headaches ,tests twice were negative but 20th march got my periods ..still feel the same ....is there are any chances i am pregnant ..or is it any other health issue..since i have never had periods delay so long ....