You've Got A Friend

(Carole King)

When you're down and troubled
And you need some love and care
And nothing, nothing is going right
Close your eyes and think of me
And soon I will be there
To brighten up even your darkest night

You just call out my name
And you know wherever I am
I'll come running, to see you again
Winter, spring, summer, or fall
All you have to do is call
And I'll be there
You've got a friend

If the sky above you
Grows dark and full of clouds
And that old north wind begins to blow
Keep your head together
And call my name out loud
Soon you'll hear me knocking at your door

Answer the following questions based on the text!

"Keep your head together", what does the sentence imply?