Hi! i had sex (pull-out method) 4 days after my period. immediately i took a plan b that next morning. my app said that my ovulation was in 3 days of that and then i started bleeding (like a period) 3 days after that. did that change my ovulation?

The wording of your post is confusing. There is no benefit of "pull out" because the erect penis is secreting sperm continuously during sex. Plan B as a hormonal surge will often change a menstrual pattern. Ovulation may or may not occur in this setting but the EC makes the system unfavorable for any pregnancy to result at that encounter.

Plan B is about 95% effective in preventing pregnancy. Hormonal imbalance induced by the drug often causes irregular bleeding. If you have concern do a hope pregnancy test 3 weeks after sex. . If the result is negative repeat the test 4-5 days later unless you get a period by then. Use first morning urine and follow the instructions carefully. Wish you good health!