In above sexual activity, there is NO chance of pregnancy
as it depends on the proper timing of ovulation and unprotected sexual intercourse with ejaculation inside vagina..
Precum or prostatic fluid causes pregnancy in rare occasion only in pulled out method before ejaculation in fertile period. Also you were involved in sexual activity in safe period (last day of her period). So, don't be much worried.
Practice safe sex
by using safe period/ OCP/ Condom etc to avoid unwanted pregnancy.
If you need further consultation with me,then you can visit http://www.healthcaremagic.com/doctors/dr-soumen-patra/63326.