Protection magic should not be underestimated

Harry didn't often get hit by his relatives, not since Dudley tried punching him and ended up with third degree burns on his fist.
Ever since then, the few times they got physically violent, it was by throwing things at him, though they also did in fact end up burnt as well.
It was weird, and according to his relatives "freaky" and he was kept locked in his cupboard whenever it happened.
Everytime someone or something was about to hurt him, they would start burning the second they made contact with him.
Then he found out he was a wizard, and that what kept happening was a protective charm that gave back any damage he would be about to receive from others. Every time someone came close to hurting him, he would feel hot all over.
Then when he looked at the books for the year, they spoke about visualizing how you felt your magic to be.
At first, all he could feel was fire, vibrant and warm fire that filled every inch of him, now he understood how it cauterized his scar immediately after getting it and the scar was nothing more than a thin white line now.
After he managed to get past the overbearing flames representing his mother's magical protection, he finally managed to get a sense for his own magic, it felt like the wind as it was constantly moving and ruffled his hair whenever he had bouts of accidental magic, later on, it made his talent for flying make sense. He didn't think that his mother's protection would act up a lot in Hogwarts, but an incinerated troll, and an ashy broomstick later, he began doubting it. But he wondered why he felt hot all over whenever Quirrel had his back to him.