You've got some issues to deal with. And, I'm not so sure they are only the ones you are thinking about.
I get the fact that you are new to your relationship and you've got a lot of personal issues, but then again, so does he. It is ALL about the communication. It doesn't matter if you're gay, bi, straight, monogamous, or in an open or complex relationship. It is all about the communication.
Now, as for your feelings, you may be moving from infatuation to love, or from first love to binding, or falling out of love. All of these are possible.
Let's not miss the fact that you are probably a little upset at him not trusting you with love. You can be attracted to him and because you're angry at not being trusted, you can be turned off. And that is totally separate from loving him.
I love my husband very much, but that doesn't mean I have to always like what he's done or how he's treated me. Or that I don't piss him off or anger him. Love and anger aren't always neat and separate.
He's right, if you leave and don't give him the courtesy of saying something, then he has the right to be angry and tell you that. His feelings in that moment are valid.
If you are upset that he is being insecure and distrustful, then your feelings are valid and you have the right to tell him.
But you two need to decide if you are going to move passed the every day minor snubs and remember what is important and if it IS important to both of you.
-K
BTW - if you've already concluded that you are meant to say goodbye, then that is a self-fulfilling prophecy.