Insecurity - Where does it come from?

One of my insecurities is my nose. It's been broken a few times, therefore, I don't like being in pictures, unless I take them myself, because only I know how to angle my face the right way. There are about a million different insecurities I could think up, but I'm certain there is more than that. So, what is insecurity, and why is it there? I can see jealousy as a motivator to do better, although it does not always turn out that way. Fear, to ensure one's own survival, anger, to push through when things are difficult. But what is insecurity? Suddenly, like a bullet to a glass window. It hit me. The best possible answer I could think of. Now, I am not a doctor, a scientist, nor do I have a degree in psychology, or human nature. I just think a lot, so this, happens to be my personal view, it has not been proven. I believe insecurity stems from one needing to be loved. Not accepted, because you can accept someone, and not love them. Unconditional love. Let's say, you were the most insecure person on the earth. But, over time, every other person on the earth began to love you unconditionally. Would you still be so insecure? Thoughts, anyone?