Hi, I Am A 21 Year Old Female. I Am

Hi, I am a 21 year old female. I am depressed and when I move I can't feel emotions or anything. Depressed was caused by what happened last night. We had anal sex however I the condom didn't fit right and precum dropped on his balls and it hit my vaj area once and I felt the liquid and we both stopped. I believe I am currently ovulating and took a plan B 3 hours after I the incident happen. What is the likelyhood of becoming pregnant from just precum hitting my vaj area and me taking a plan B. The other question is that this is the time I am normally ovulating but I have an irregular period so I am currently asuming that I am ovulating. Does plan B have any effect on me if I am currently ovulating or did I take it for nothing and feel nausea for no reason. I am not on birth control pills. Please help I am like a person without a soul and the anticipation is horrible because I probably won't be able to pee on a stick until a week or two.