Hmm. Last paragraph first: No, it isn't typical 10 yr old behavior. It's funny you posted this today, because my 10 yr old daughter just got her new bed (frame) delivered this afternoon.
She'd had a hand-me-down twin bed since she was 2 1/2 yrs old or so, and was quite content with it. Until the mattress started to feel lumpy to her a few months ago. She actually asked to sleep on her floor. So we started shopping (hubby and I). Thought I could fit a full sized bed in her room, with some rearranging of stuff, and priced out some that I thought would compliment what is already in her room. Shopped for the amount of $ we had to spend on it and found that I could find something in that range. Found a great deal on a mattress set and went ahead on got that (took 3 days for them to get it delivered), and put it on the floor. THEN made a final decision on the frame itself about a week later.
My daughter only had minimal input. I narrowed it down to what I thought was best, and asked her if she would be ok with it. (yes). It was ordered and paid for in mid-December. She saw a picture of it online... that was it.
It came today. It is pretty tall and she looks like the princess and the pea, lol. BUT, she NEVER got whiney, or bossy or rude or anything about "when is my bed coming?" She asked once or twice, but it was for information--not complaining.
Now, for the earlier parts of your post, it sounds to me like YOU are the one who really wanted to get the new bed for her. It was all your idea and she doesn't really NEED it, it just was something you wanted to do to be nice to her. Right? So she can keep her toys out and not have to put them away?
But now she is having a fit because it didn't happen RIGHT NOW. I'd wait. Just tell her that her behavior and attitude have given you time to reconsider the entire idea. You wanted to do something nice for her, but you got sick. Something out of your control. If she isn't mature enough to grasp that, and to not trash her room in anger, then it really doesn't make sense to spend unnecessary money on something expensive for her room---that she may just decide to trash in anger over something else. Sorry.
Be prepared for the screaming. She MIGHT take the apologetic tactic---but I'm not sure. It depends on how serious she is into her pouting I guess.
But, look at if from her perspective too.... did you approach her out of the blue and wind her up about shopping on Saturday and then at the last second cancelled? How big of a deal did you make it out to her to be? If you played it way up, then that is what is causing a lot of this. Pouting a little is normal, but sulking and bad attitude for more than 24 hours is a bit beyond normal for unspoiled non-bratty kiddos.
She is 10. Have you explained the mechanics of going shopping for it, making a decision, dealing with a salesclerk, placing the order and then WAITING for it to be available for delivery? She should be able to have the patience for all of those things....
I learned a long time ago not to over-play things to the kids. They can get excited enough all on their own without me stirring them up. Then if something goes wrong, it is easier to ameliorate the damage, because it wasn't treated as a big deal to start with. I try to keep things matter of fact. I prefer them that way myself for me, too. Don't tell me a movie is amazing--because then, even if it is really pretty darn good, my expectations are sky high and I will end up disappointed. Kids go through that, too.