Hello doctor, I had sex with my boyfriend on 13th May,2 days after my periods were over.There was no penetration,but my boyfriend came on my stomach before which there was rubbing of his penis on my vagina.Fearing pregnancy, I took an i-pill after 18 hours.I had my periods on the 22nd of May with mild spotting and bleeding.I also had fever during the same time. My next period has been delayed by 5 days.(It is supposed to have occurred on 18th of June). Do I have to worry about pregnancy? I have so far had no other symptoms of pregnancy like nausea,food cravings etc.,My pregnancy test results on 23rd of June are negative. (hCG one step immunoassay rapid test).