Feel like a bad mom

Another one of those days.  You know the kind, where you don't want to get out of bed or do anything after that.  I woke up before my alarm and got myself ready to start the day.  I came down stairs to see that I never did wash the dinner dishes last night. What a let down.  Then I find out I have to fill out a paper for the little prince's school about parent teacher conferences that needs to go back today.  After that I tried to get him out the door, but he didn't have either of the sweatshirts I sent him to school with last week.  He adamantly claims the black one must be here somewhere because it isn't in his locker. I remember sending him in it so I know it's there at school.  I told him to look in the lost and found and he smacks his forehead with his palm.  This was just a little too much for me apparently, because I blew up at him.  I feel so terrible about this.  I even made him cry.  I almost cried myself as I apologized and hugged him.  He buried his face in my neck and asked my "why" over and over.  I tried to explain to him how I was feeling, I told him that when he acted frustrated with me it made me feel like he thought I was stupid and nobody likes feeling that way.  He assured me it wasn't what he was thinking and not what he meant.  He told me he was frustrated with himself for not making himself clear. That was the first time he ever said that.  Communication has always been an issue, but this time that wasn't the problem.  The problem was my attitude.  I need to work on that.