Why my kids make me feel like the worst mom in the world

I'm going to start this post by saying that in reality I know I'm not a horrible mom and most of the time my girls are good.

But every once in a while, like RIGHT now, they make me want to bang my head against a wall and run away.

This has been my feeling the past few days actually.

I don't know who they are or where they have learned some of the things they come up with.

I have taught them manners, and I thought I taught them respect.

But I have noticed NONE of that this past week.

They are annoying the crap out of me.

And I know that sounds horrible but really.

Most likely they are bored.  It's been too hot to go outside and play and I've needed to get things done around the house.  But they can't figure out how to entertain themselves at all without fighting or screaming or getting into trouble.

Where have I gone wrong?

What happened to everything that I thought I taught them?

I am truly a horrible mother for having children with me in a store who beg and whine for everything they see.

There is still plenty of summer left and I can not take this kind of behavior anymore.

I've tried speaking to them about there behavior.

I've threatened to send them to summer camp.

I've begged.

I've cried.

Why are they doing this to me?