Macbook boots twice every time it starts
I have the latest Macbook 13' bought in 2013. I noticed that recently every time I start or restart my Mac, it boots twice. I would be prompted to enter the password after the launch sound and then after I enter my password, a bar appears and when it loads to full, my Mac would restart and repeat the process, asking me to enter my password again. This time without the launch sound.
Is this normal?
MacBook Pro with Retina display, OS X Yosemite (10.10.2)