I ejaculate inside her and she have spotting . she expect also her period this week . how many percent she can get pregnant ? shes regular 30+d cycle

Fertile window: Is the time when unprotected intercourse has higher chance of conceiving. Here is a calculator you both can use based on cycle. https://www.babycentre.co.uk/ovulation-calculator The spotting after intercourse is called postcoital bleeding and this does need to be checked out by a doctor licensed in your area as need to exclude a number of medical conditions

"Percent is variable: If she is young, healthy, has normal ovaries, tubes, uterus and cervix, and if you "ejaculated once inside her" about the time of her ovulation and your sperms are also healthy and normal, there is perhaps a 50 to 70 % probability that "she can get pregnant" during this one cycle. Probability increases with "frequency and time" and decreases if ejaculations are mistimed, if anomalies exist...etc.