I have 30-35 days cycle and ovulated around day 21 this time, what s the high chances of pregnancy or fertile window, my egg size was also 21 mm?

Fertile window: Your fertile window is around the time of ovulation and usually occurs 14 days before your period starts. With a 35 day cycle length, this would be day 21 so everything appears normal and would give you a good chance of pregnancy providing you had intercourse around the time of ovulation if there are no other problems. Best wishes.