Kelli - well as a mom of 4 boys, I have more than my share of bad mommy stories ... but this one happened this week (including a couple very similar to yours

).
My son Tanner, fell off the monkey bars and really hurt his arm. But my husband was at work for the evening and I was home alone with the 4 boys -- and I really, really didnt feel like sitting in emerg. for hours with the kids ... So, I put ice on it and hoped he'd be ok. He calmed down and seemed "fine" so all the boys had supper and went to bed.
10pm up awakes my hysterical son in agony from his "fine" arm. Called my husband at work who came home and took him into the hospital for me.
Apparently, it was BROKEN!!!
Ahhhhh ooooopppps.

But what has made me feel better is how many other mothers have told me it took them a day or two to realize their child had probably broken a limb!
Jen