It is vexing, I understand, son, but by nature of who he is, and the belief that at Hogwarts he is attainable, he is like to become a target. There are a number of people and organisations with an interest in seeing that he comes to harm.

As for your part, it was perfectly plain that you were doing what you could. Your beaters could have been more on the spot, as well - a fact sadly lost on your captain, it would seem. (Though not, I will note, on the opposing team's beaters.) It was a good instinct to impose yourself in lieu of being able to beat the bludger away. However, as unacceptable as it would have been to allow Harry to come to harm, it was equally distressing to your mother to see you attempt something so dangerous quite so often!

Nonetheless, you acquitted yourself well on the pitch, son, and we're both very proud of you.