You did exactly the right thing. You refused to be victimized! That says to me that you are stronger than you think you are. It is absolutely not your fault that this guy was inappropriate with you. His job is not your responsibility. You didn’t put his job in jeopardy. He did.
It doesn’t surprise me a bit that he is “much loved.” If he is an offender, he works at bringing kids into his orbit by being extra kind and offering help. Lots of teens go through difficult times and are therefore emotionally vulnerable to someone who seems sympathetic. Sadly, not all helpful adults have pure motives. My guess is there are other kids who have also been approached, but who didn’t speak up. I certainly hope the school is going to investigate further.
Please hold your head up high. You have every reason to be proud of yourself. Not only did you resist this guy’s attempts to get inappropriately involved with you, but you may well have prevented him from victimizing someone else. If you are still upset when you get this reply, please ask your mother to make an appointment for you to see a therapist. You may need a little more support for awhile.
I wish you well.