Giving God my worst?

I have had a few really bad days this week. Now, of course, bad days are unavoidable. I tell my kids that all the time. Still, I wish I could avoid them. I don't like feeling crabby. I don't like feeling frustrated, or tired, or annoyed. I don't like these feeling, but I do usually give in to them. Furthermore, I make sure EVERYONE around me knows I am suffering through them. Then, I end up feeling guilty after wards. I really don't like feeling guilty after wards, knowing I should have been more patient, more understanding, more selfless.
So, what do I do? Do I stay in bed on those bad days and avoid the world like I want to? Sometimes, I think that would be best (though not very realistic). Instead, I need to try to unite my suffering, small though it may be, to Jesus' suffering on the cross (as one of my "twitter" friends suggested). It is hard to believe when I am in the midst of my crabby moods that God can really use my suffering for good. It is true though. There are those who can not help themselves, helpless souls in need of prayers and sacrifices on their behalf. What a better way to glorify God on those days I barely feel capable of it, than to remember and suffer on behalf of the least of God's children. So, I hope in God's time, it is not too late to offer all the difficulties I have endured this week, for those most in need. I hope God will take my meager sacrifice and use it for the good of others. As much as I might like to, I cannot avoid grumpy moods or challenging days but I can still glorify God in my compromised state of mind if only I offer it all to Him.