He will be horrified at the thought of what he’s done, will be nauseated by the very idea. But not now; only after.
After he’s finished downing as much as he can as fast as he can. After he’s become swollen with need, stretched taut with potential, hungry for emptiness. After his aching lows have given way to rapturous highs. After he’s slipped seamlessly from euphoria into slumber. After his own arousal, a full ten hours of sleep later, brings with it vivid memories of everything that he did and everything that was done to him from the moment he first lifted the bottle to his lips.
Then and only then will he feel frightened and ashamed. Shame at the thought of how much he wastefully spilt down his body in his eagerness to take it all in. Fear at the thought of having to wait another week until he is dosed and milked again.