I hate being a boss!

I have a total of 2 people that I directly supervise which I realize isn't as bad as it could be, but I don't like having to be the boss! The problem I have with it in this job is that I have to do the same things that they do, so I understand what it is like for them, the bad part is, I still have other people telling me what has to be done. Both of the women that I supervise are older than I am, and have been there longer than me and that makes it even tougher. Plus if everyone doesn't get along, we still have to spend 8 hours together in a tiny room and it can make things a bit uncomfortable. The problem I had tonight is I had to ask one of them to relieve a person in another area; it usually isn't a problem but she had applied for the job when it was available and someone else got it, the woman who was working tonight. The woman that I supervise had a FIT, yelling at me and saying that she wasn't going to do it, it's not in my job description, blah, blah, blah....and for the most part I agree with her. BUT, the lady in the other department still deserves a break too, and it isn't her fault she got the job, and it kind of is in her job description right at the bottom where it says, just like mine does, "and other duties as necessary". All of us disagree with some of the things that we have to do, and there are parts of the job that none of us like, but the problem is this woman is not licenced and the rest of us are, so there are things that she can't do and we can. (the place she had to cover doesn't require a license, it is basically an operator job) There were 2 other people in there while this was going on, and she finally did go do what I asked her to do, but I felt like I was the bad guy! I wound up having to call my supervisor at home and explain what happened so she would be prepared when the proverbial "poop" hits the fan tomorrow! This is Monday for me, and not a very good start to my week! :(