Is this normal?

First of all, I have been cleaning all day. I cleaned both bathrooms, dusted, cleaned the kitchen, vaccumed, did laundry, and even got down on my hands and knees and mopped the floors by hand. Believe me, if you've been to my house lately you know how badly it needed to be done. So, I let the kids stay up a little later than usual for their nap because I wanted to vaccum before I laid them down. So they ended up laying down about an hour late. All I wanted to do was sit, relax and get some homework done.

Then, I was sitting doing my homework and I heard Declan "Moooommmmmmyyyyy" so I ignored it, they had already been in bed for about 45 minutes and he should have been sleeping. Then, I heard it again, "MMMMOOOOMMMMMMYYYYY" so I went in there only to find he was refusing to take a nap and just trying to get me in there to "tell me something". I was pretty aggrevated that he hadn't gone to sleep yet, but seemed to keep my cool until I realized that in the process of him yelling for me, he woke up Alaina. I was LIVID. I had never been more angry at him. Now, not only is Alaina crabby because she only got a mere 45 minutes of nap time, but he is also crabby because he won't go to sleep if she's awake. UUUUUGGGGGGHHHH the "joys" of being a mother.