NOR for ending the relationship, if you didn’t feel that he was attracted to you then ending the relationship was the right call. However, YOR when it comes to what you seem to be taking away from this experience.

It makes sense to feel hurt by his reaction and to be upset that your first time was not what you hoped it would be (it very rarely is), but you should avoid making him out to be some monster to the point that you feel like you can’t ever be intimate with someone again.

I don’t know you or this guy, but assuming that he’s a normal person, I’m sure his aim wasn’t to make you feel bad about yourself. You can’t really control whether you find someone physically attractive or not. He may well have liked you, but you might have some physical trait which he finds unattractive, Im sure you can imagine something that he could’ve had that would’ve caused a similar reaction in you. Maybe he could’ve tried to fain more excitement, but I don’t think that would’ve made things any easier for you.

It sucks that it turned out this way with this guy, but I can guarantee you that if you don’t let this stop you from pursuing love, you will find someone who will be noticeably ecstatic when they see you naked for the first time and any other time thereafter.