When my kids are out of sorts and I recognize it and can connect the dots and understand why, I cut them some slack. I'm curious as to why you felt a strong need to "control" the situation. I probably would have said "wow you sound cranky. Feeling tired, eh?" And if she continued in her original cranky tone, I would have said "sure I'll turn on the shower for you because I can see that you're not yourself right now. Let's get you off to bed and start fresh in the morning."
Sometimes kids fall apart. It's OK to show them some kindness. Haven't you ever had a bad day when you just wanted to do something other than what you had to do because you were tired, frustrated, having a bad day etc (watch TV when you haven't done the dishes yet, or eat ice cream or waste time on-line instead of doing what you're supposed to do)? Isn't it nice when someone like your husband recognizes that and says "it's OK hon relax and I'll take care of..."? Being nice doesn't automatically mean that someone will take advantage of you the next day when they're back to themselves.
I'm also curious as to why you "ask" your child to take a shower. Asking implies that "no" is an answer and given the way you describe the rest of the interaction, she had no choice. So if you are really telling her that it's time to shower, then tell her and don't falsely ask. In my house, I generally do "ask" about showers because I don't care what the answers is, I need logistical information. "Are you taking a shower tonight" or "can you take a shower now" means exactly that. If the answer is no, or "I already took one earlier" or "I'll take one tomorrow" then that's that. I honestly don't care how often they shower - they're the ones living in their bodies and after a certain age, it's their responsibility to decide if/when to shower, within reason. If my son comes home from hockey and wants to go to a family function without showering first then I point him towards the bathroom but on a daily basis, as long as they're not noticeably dirty I don't care. If your expectation are such that tonight was a night she had to shower, then I wouldn't have asked her to do that, I would have reminded or told her.
My oldest has ADHD and sleeps poorly because of it. I can usually recognize when he's being ornery because he's tired. If it's self-induced exhaustion from sleeping over a friends house and staying up too late then I cut no slack but if it's because his brain and body couldn't rest, I react the same way that I would if he had a cold or was under the weather. It's not OK to be rude to me, but I will let a temporary lack of grace slide and remind him to get some rest or try to get him to take a nap. I know that I appreciate the same when I'm not at my best either.