No seen in TVS but positive

Hello All! My LMP is January 26, 2024. I took 1st pregnancy test last March 2, and the may faint line po, so naisip ko po na baka maaga lang to take a test, March 3 I took a test for a second time and positive po, then took a test again last March 5, and positive po ulit. March 6, I took a ultrasound, pero wala pong nakita na kahit ano. So I decided to take a Pregnancy Serum, and nag positive po. Am I pregnant po diba? Since sabi po is mas accurate po yung Pregnancy Serum, pero bakit wala pong nakita sa Trans V ko? Thanks po.