Eh sayang, this sounds so stressful and confusing! Honestly lahhh UPT results boleh jadi inconsistent especially kalau hormone levels still rising or falling, a few of us had similar experiences where one day samar-samar, next day takdatang, so it's not just you. That one-day bleeding tu boleh jadi implantation bleeding or just hormonal juggling, but paired with the samar line on Clear Blue then negative again, I think you really need to see the doctor again and ask for a blood test (HCG quantitative), tu yang paling reliable, not just urine tests yang boleh confusing. Since your scan showed thick uterine lining, the doc can check if hormone levels rising or falling to give you a clearer picture of what's happening. Jangan stress guna banyak UPT lagi okay, one blood test will give you the answer for real.