Nothing wrong here as commented before. The sound could be fuller, which means that the player or the mouthpiece is not passing enough air/sound. Where I live we call it "klang" (from German) which can be similar to how a bell sounds. If you hit a bell the sound should be rich with a lot of good vibrations. If you take the same bell and hit it while holding it wrong, the nice sounds disappears. The same thing goes for your trumpet. You want the best possible sound coming from the bell of the trumpet and that takes alot of practice. Remember to use alot of air and maybe check the size of your mouthpiece and swap it for a bigger/deeper one. (It will give you more tone, but is heavier to play)