I Got Period On 28 January And Stop On 2

i got period on 28 january and stop on 2 february.i had intercourse on 5 february.i took postinor 2 on 6 february at 2.30 pm and then took 2nd tablet exactly 12 hours after 1st tablet.after 3 days took postinor 2, i got bleeding for 7 days.until today iv not seen my period.did test on 21 & 24 march,it's negative.did i got pregnant?