For one, I think you need to accept responsibility for your actions. If you're 18, you're well old enough and seem to remember far too much to blame it on alcohol or being taken advantage of. You may have made a poor decision in sexual partners, but that's part of life and the sooner you accept responsibility, the better of you're going to be. If you're 18, you're an adult and your sex life is entirely your own private business. It may be embarrassing but all you can do is live and learn from your mistake and perhaps leave off one night stands and picking up people at clubs.
If he's a Teacher, he's likely just as worried about you and what you'll do as you are about him and what he'll do. It's unlikely that he's going to tell many people about what happened as he could lose his job for it easily. He's not a Teacher at your school so I wouldn't honestly stress so much about it. You may never see him again.
Take a deep breath, laugh about the poor decision, learn from it and move on. Many people have at least one bad partner in their life that they regret.
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Holly.
Mama to Hunter Kai
Still missing you, LML. (1941-2007). ♥
"Nothing is worth more than this day."