Growth spurt?

My baby girl will be 3 weeks old tomorrow. Yesterday & today she has been eating nonstop.(bottle fed)and barely sleeping any unless I hold her.

Could this be a growth spurt? I know two days ago she slept longer than she usually does and didn't eat as much as she usually does... the next day she woke up doing this.

She was drinking 3oz every 2-3 hours. Now every hour she's crying for milk.. and she will drink anywhere from 1-4 oz at a time.

Oh, she's like this all day then about 5-6 in the evening she goes to sleep for 4-5 hours and then sleeps 2-3 hours a time at night between feeds.

I guess I should be happy she knows her days from nights, lol.