I think the positive thing is, the guy doesn't seem like a complete asshat. The fact that he did try to 'make up' for his ills the night before atleast shows that he is somewhat receptive and somewhat committed to you and the relationship. However I do understand your point, and I sympathize (I'm a very sensitive person, I take most things to heart).
I think his behavior could be manifesting for a few reasons. First off, is he actually under stress in other elements of his life? Is work/study difficult? Is he having issues with anything? You might not know the answer because he simply might not have told you about what could be going on - the fact that he said he was "stressed" and wasn't into your plan because he wasn't in a "good mood" could demonstrate that his actions are due to an external force, not you and not an element of his personality. Perhaps sit him down casually, even just bring it up in conversation and say "hey, is there anything you need to get off your chest? You said you were stressed the other night?" He might feel like he can't express those opinions to you openly, he might be feeling trapped.
Secondly, you say you've been dating for about a year. Perhaps you see the relationship at a different point to him - perhaps you are taking this length of time as a sign that you are both very serious and hugely committed to each other, where as a year in his eyes could be a 'this is going well, lets see how it keeps going, shes lovely' type of thing. Relationships are give and take, and although you may be expecting him to be enthusiastic about everything you want to do and want to plan, he might still be at the stage where he's not going to drop everything for you. Maybe you are simply expecting too much of him at times, and although you may see his reaction as a sign of indifference towards your emotions, he may simply just be tired or stressed and not understand why you can't understand that.
Thirdly, it could be an aspect of personality, which unfortunately is not something you can change. Perhaps he really is just a bit oblivious, a bit too immature for a long term relationship, or not that great.
I think you should give it a bit of time, and try to communicate in a casual setting. If you get too heated or emotional he will feel overwhelmed and won't take in what you are saying. Ask him if he has anything he's upset about, stressed about etc, and if he says no then explain how this incident made you feel without going into theatrics.








