I've done te same thing. Once I dropped a salsa jar and broke it and before I even knew what happened I had a piece of broken glass in one hand and my other arm was bleeding. And I wasn't upset, I wasn't hypo, I wasn't depressed...I just saw the broken glass and went for it. But I forgave myself. You did the right thing by going to the ER. You only scratched yourself, you didn't hurt yourself badly, you were able to catch it before it got to that point. We all have slip ups from time to time. You handled it the right way.