While the embouchure and aperture are very important, without adequate lip vibration the true sound of a trumpet is absent.
That stated, in ascertaining your valves are inserted into the casings properly, other than the numbering, you should note a valve guide on each that aligns with a groove in the casing.
Your director depressed the first valve and you should have heard (with Bb music) an F then Bb, and lastly an F again all within the treble clef. In concert key, as you read these on a chromatic tuner they would be Eb, Ab, and Eb again or a whole step down as would be played on a piano, violin, or other C pitched instrument (and what you're actually hearing).
Tell us what brand and model trumpet you have! If you don't know the model, provide only the first 3 numerical numbers and any alpha prefix of the serial ID found on the second valve or on some Bessons on the underside of the bell near the valve block.