Plan B question?

Hello everyone.

We are actively trying to avoid pregnancy. I’ve been on the pill but due to a lot of break through bleeding and side effects decided to switch brands. My husband knew I was switching brands but I forgot to communicate with him that there would be a gap due to shipping times of the new pills. He did not pull out or use protection today and I am currently not on birth control and it’s been 1 week since I have been. I took an ovulation test to be safe and it was positive.

If I am already ovulation, will plan B even work since it works by delaying ovulation? I plan on taking it either way, but would love some input on timing. Thanks!