Hi I Got Married On 22 Feb.this Month Am Not

hi
i got married on 22 feb.this month am not getting period.last tym i got my periods on 25th of feb. i had an unprotected sex on 24 then i took i pill but den again i had unprotected sex on 25th and 26th as well. i did pregnancy test as well but result was nevative. what should i do to get my periods immediately and to avoid pregnancy if there is any chance of it