Hello , i am 21yrs old, recently i had intercourse with my partner, we tried the withdrawl method , i had my past periods on 31st augst, my nxt due was between 28th sept, i had my intercourse 9days before my nxt period time , now i missed my period, immediately i tested urine home kit , my result was negative all the time , bt still my periods is not occurring ,could i be pregnant???