So, backstory. I work Security and have for about two years now. At one of our sites, I'll refer to as S, I was there for about 8 months before the contract got sold to another company and I went to another site. Fast forward 4 months, I quit and went to the company that got site S. 

One of the first people I met was a former, now current, coworker. He works 1st shift, I work 2nd shift. 1st shift is a nightmare mess anyway, but yeah. 

I am a bit of a workaholic, and in my second and third week, I've taken on 36 hours of Overtime, my gf moved to another state for school, and it's just me and the cat, so I spend a lot of time working, simply because it's a better use of my time (college is in the works but I am in a bit of debt by biting off an apartment more than we could chew and I will be moving, but I gotta stockpile cash) than sitting around playing video games or whatever. The coworker, referred to as W, only works 25.5 hours a week. 

I come in today, and my supervisor comes in very soon after, because he was checking in on the building. As soon as he comes in, he asks me why I've been late every day since I started. 

Well, this strikes me as odd, and my coworker for my shift backs me up, saying I've never been late working 2nd shift. In fact, the only time I was late, I made certain to call and let the supervisor for that shift know I was running behind schedule. 

Supervisor then tells me "Well, W on first shift calls me every day and blows the supervisor phone up complaining that you're always late."

So now I plan on making certain to show up early, and make sure that everything has been done to a perfect T, and should anyone leave even a second before their scheduled time, I'm reporting them for abandoning post, as I have not started my shift, and will not be held responsible for their carelessness, while simultaneously dragging my name through the mud. 

Would this make me the asshole, considering I will be as nitpicky as humanly possible, to the smallest detail? 