So, I started a research project with my professor some time back. I suggested that we apply for an undergraduate research award and so we started discussion on it, and we narrowed down our problem and all. Then I suggested that I find some other undergraduates to collaborate with on the project and he agreed. I looked around for some people who were interested, and I found someone I knew who was quite enthusiastic about it and I hooked him in on the week that we started working on the submission for the research award. I typed out the initial draft where I didn't think much about it and typed my name in front of his. I mean, it is true that I started the project, call the shots/make the major decisions, and am the senior of the two of us - but I don't care that much about credit - at that it was only because I was more familiar with typing my own name. But some time afterwards, we were writing the paper side-by-side (he was typing) and I told him let's format the cover page. In the process, I thought a while and suggested, let's put our advisor's name as the first author because we'll rank by merit, and he agreed and shifted my advisor's name ahead of mine. Then I told him to line our names horizontally instead of vertically because it's the proper formatting. So at this moment, he pasted his name ahead of mine - then fumbled saying something about alphabetical order looking nicer. But of course, he knew the implications of that because we agreed to putting my advisor's name ahead by order of merit/seniority in the first place. Besides, my advisor's name is still out of the sort-called 'alphabetical order'. So from being not really concerned about the naming order, I felt a little annoyed that he came up with this strange device just to put his name ahead of mine. OK, let's just say now I'm bothered by it because it's starting to feel unfair to me. I'm also bothered that he might be trying to covertly imply that he did equal or more work. I didn't want to kick up a big fuss about it because I've had an amiable partnership with him so far, so I told him "It doesn't matter for now," and got on with editing other parts of our submission... but now I can't think of a right way and moment to bring it up again and rectify it without making it awkward for both him and me at least! What should I do?