to take plan b or not

My boyfriend & I had sex today. He thought he felt the condom break after he finished & checked & said it was nothing & left it by the night stand, so after about 30-45mins I went check on it to make sure for myself & it felt a little wet from the outside & I asked him to feel it & he said it was the lubricant but to me it didn't really feel like that. I am kind of nervous & I am not sure if to take Plan B or not since it's pricey...
Update: I did end up taking it, my friend took me to get it. You girls were right, It's better to be safe than sorry. Thank you girls 💕