Is plan b effective???

Hello, I wanted to ask about plan b and if someone had same experience. So I had sex with my husband on Thursday 30th and he came inside(keep in mind it’s ovulation week according to app) so the next day the 31st we bought plan b and took it around 2pm, later in the day around 10pm I felt a sharp pain on my right ovary that it almost made me throw up 🤢 ( I feel similar pain every month when I ovulate) since it was new year’s eve I was drinking alcohol beverages so would alcohol affect any way the effectiveness of plan b and does plan b cause pain?