I have an irregular period I had my period last on the 24th April and ended on 29th April 2016 and on 19th may I try to have sex there was no penetration he released under my butt and I had a period tracker which I had just download right before my my period on the 24th April in the tracker am supposed to have my period on the 22 may so I got a pregnancy test done on the same day am suppose to have my period and it was negative could I be pregnant cause my period changes all the time help.