Possible plan b fail?

Heyyy so according to glow im 6 dpo… prior to this i had unprotected sex with my husband some days ago an we slipped up. Took plan b less that 24 hrs after for the first time. According to the app I wasn’t expected to ovulate until about 5 days after that night….but the next day during the day clear stretchy mucus was present and that was d only day I saw that! Been have nausea and very tired during the day. What are my chances of concieving?#ps I hv a 8 month old . Thnks in advance😣