Entity position problem

I created an entity at a specific point, and then I set it on motion. But after I set it on motion, it's position that i get from it is still the position that i created it, not the position after i set it on motion. Help!

It should actually work, what are you doing wrong?

IDK, should i post my code?

Yeah please

PHP:

        $player = $p;
        $nbt = new CompoundTag();
        $nbt->Pos = new ListTag("Pos",[
            new DoubleTag ( "", $player->x ),
            new DoubleTag ( "", $player->y + $player->getEyeHeight () ),
            new DoubleTag ( "", $player->z )
        ]);
        $nbt->Motion = new ListTag ( "Motion", [
            new DoubleTag ( "", - \sin ( $player->yaw / 180 * M_PI ) *\cos ( $player->pitch / 180 * M_PI ) ),
            new DoubleTag ( "", - \sin ( $player->pitch / 180 * M_PI ) ),
            new DoubleTag ( "",\cos ( $player->yaw / 180 * M_PI ) *\cos ( $player->pitch / 180 * M_PI ) )
        ] );
        $nbt->Rotation = new ListTag ( "Rotation", [
            new FloatTag ( "", $player->yaw ),
            new FloatTag ( "", $player->pitch )
        ] );
        $nbt->Size = new IntTag("Size",0);
        $speed = 3.0;
        $slime = Entity::createEntity ( "Slime", $player->chunk, $nbt, $player );
        $slime->setMotion($slime->getMotion()->multiply($speed));
        $slime->spawnToAll ();

What's the problem?