possible pregnancy?

4 days ago po nag PT ako, it resulted with 2 lines the 2nd is faint. So i repeated it after an hour and a half, and the 2nd line is mas faint pa than the 1st, it's almost none. I bought blue cross and tested the following day early in morning. It has 2 lines and the second is visible but is faint same as the result of the first test. A day after i decided to schedule an appointment with an OB as i was experiencing lower abdominal pain as if having dysmenorrhea. Technically it was just 4weeks po since my LMP. Pero sabi ni OB wala sya makitang signs of pregnancy when she performed TVS, but she remarked that my uterus is thick.. pinababalik nya ko sa 22 for ff-up. Ano po kaya sa tingin nyo? False possitive lang ba PT result ko or sobrang aga lang talaga ng detection kaya wala pa sya makita? Thank you po in advance for answering.