Had Foreplay Without Ejaculation. Still Took U-72 Within 24 Hours. Having Delayed Periods. Pregnancy Test Negative. Chances Of Pregnancy?

me and my bf genital area touched for 10 second without any ejaculation and intercourse . after that he ejaculated and he was wearing breif andi was wearing panty on 23 nov.but still i took U-72 on 24 nov within 24 hrs. and my previous periods were on 31 oct and i got my periods on 1 dec. but till now ,my periods haven t come yet.i haven t experienced any symptom . i took home pregnancy test yesterday and it was NEGATIVE. is there still any chance of me getting pregnant?? my question are?? 1 am i pregnant??? 2 is there any need for blood test 3 the incident almost happened 1 month ago,and i haven t experienced any symptoms,after how much time symtoms starts to come??? 4 are home pregnancy test accurate or reliable?? 5 how much long should i wait for my periods to come??? 6 what are the first pregnancy symtoms???? 7 is it still possible to get pregnant after having periods after that incident and almost one month with no symptoms?? please help me ...m really worried