I'm 17 Days Late on my period.. The last time i had my period was April 21-25th. According to the <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> i ovulated through May 4th-10th and according to my flow app May 4th-17. According to both apps my period was supposed to start on the 23/24th of May. It is now June 9th and still no period.. I took a pregnancy test on the 25th of May and it was negative. Should i re test? Doctor? Help