Wondering Why

I've never heard a definitive answer on wheter or not it is okay to question God. I am having a bit of a struggle today.
Yesterday, our realtor called and said they were going to show our house today. So we busted our butts to get the house as perfect as we could. I guess you can imagine that cleaning around four kids is no easy task. So we are dusting everywhere, picking up the piles of stuff that has the tendency to accumulate over the weeks, straightening up, finishing laundry, trying to make the house smell more inviting, all those things we all do to try and get our houses presentable.... or at least I do. My house does not stay clean!!! I stressed that to our listing Agent, and supposedly they are going to respect that.
So this morning, I loaded all my kids up, plus two of my babysitting kids, and went to Mom's to hang out.... it's 2:00 p.m. and I'm still here!!!!! They called this morning, and said that the other agent that was to show the house cancelled on them, but they might have another showing this afternoon. I had asked our agent to run by and take pictures since the house is clean, too... So here I am hanging out at Mom's with six then seven kids, my other babysitting kid came later, and waiting to hear when we can go home.
Then she calls and says the lady looking this afternoon, has a 60,000 limit to what she can afford, and our house is priced higher than that and we can't afford to drop the price that much.
But then just a few minutes ago, our agent calls, and says when can I show your house?? aaaaahhhhhhh
Anyway, recently, I have once again been struggling with fear that things are not going to work out with selling our house, and getting our new house once its built, and things like that, now that the new house is getting closer and closer to being finished... Some of the same fears that I'd had back in June. Mom showed me the note that I had written to myself the night of the Bible study at Billie Sue's. I think I need to get that out and staple it to my forehead.... maybe it would sink in then.
Today I was upset, because I always get my hopes up when someone looks at the house, and when they cancel, I get upset again... I guess I wonder what the purpose is in that, and what God could be trying to teach me through this. I mean ultimately, He has control of everything... so why let me get my hopes up about something only to have them dashed??? I don't know, maybe He's trying to teach me patience and trust, only two things that I can't seem to get a grip on... I guess that may be the answer to my pondering.
On the flip side, I feel guilty that I even stress about this when so many people around me are dealing with circumstances much more difficult than my own, with sickness, cancer, financial difficulties, and other things. Right now I feel that we are very blessed and I have no right to feel the way I do.
Anyway, I'll be praying that God would give me peace in the midst of this storm, and that I would learn to trust Him no matter what.