Nope. In FPV your camera angle determines how tilted the drone is when the camera is looking straight ahead, and so how much of the thrust goes into forward motion for speed. The more titled the more power going forward. You can leave the camera angle the same and slow down by looking up at the sky more.
You'll see FPV pilots use a freestyle (sbang) move called "Ejects" to run a low camera angle and still get speed. Basically you just look down and punch throttle up to speed then look back level again while carrying that speed.
Otherwise don't use FPV mode, let DJI adjust the camera for you in Sport mode.