So I work at a help desk where I'm the only employee around and there is no supervisor for the majority of my shifts.
My supervisor recently informed me that my co-worker (whose shift is directly after mine) sent her an e-mail complaining that I was leaving snack wrappers, etc. around the desk. A couple of months ago, this same co-worker told my boss that I had left early (I believe at the beginning of the year I had informed my co-worker that I had to leave around 5ish minutes early to get to another job). I didn't really get into any major trouble, my supervisor just mentioned to me later that I should stay until my co-worker gets to the desk and to clean up.
However, I found it extremely rude that she went behind my back. I am wondering if I should confront my co-worker about it and ask her why she didn't bother to work anything out, especially since the snack wrapper thing could have been a quick conversation and not involve my supervisor. I myself try to make a point of not bad mouthing my co-workers. For example, if I suspect them of not showing up for a shift, I will ask them one on one about the situation instead of immediately e-mailing my supervisor.
Any comments or advice in what to do in this situation would be extremely helpful.