Zuli, a 29 year old woman, has been in a relationship with her master, Qong Kiu, for several years. They are sexually active and use condoms as their primary form of contraception. During a weekend getaway in Daguanyuan three weeks ago, they had unprotected intercourse through Saturday night, which Zuli estimates was around day 12 of her cycle. Zuli recalls that her last period started four weeks ago on a Monday, and lasted five days. She has not experienced any unusual symptoms like nausea or fatigue, but she did notice slight breast tenderness yesterday, which she attributes to her period possibly arriving soon. She took a Q Corp pregnancy test this morning, which showed a negative result, but she’s unsure if it’s too early to trust. What is the likelihood that Zuli is pregnant?