I don't think the realtor was rude for asking, and I don't think you were rude for telling her that you'll need more time in the future. Was this someone else's realtor, or the one who is helping you try to sell your house? If the latter, I do think you should have told her ahead of time that you'd need an hour to get the house ready when she has people who want to see the house.
I try to keep my house close to company-ready (not Queen of England company, but friend-company) because I find it really easy to get waaaay behind on housework if I slip just a little bit. But when we were trying to sell our house, I felt like I was constantly on edge, trying to keep it clean. It really is exhausting. The kicker? We had ONE showing before we finally moved out. But I never knew when there would be a showing, and I really didn't want to turn anyone away; that could be the one person who would buy our house.
However, it does depend on how motivated you are. Selling our house is a huge priority for us (alas, a year later, and we STILL don't have a buyer; it's one of the worst areas in the state to be selling a house right now). If you have the funds/time/whatever to wait to sell, then you can afford to be a little more choosy about the timing of showings. But you want to get rid of it as soon as possible, it is pretty normal for realtors to have people who want to look at a house last minute.