All really good advice here!

I'll just chime in to say that you might consider, for now, leaving the pinky out of the exercise. 

This will let you work on the three other fingers of the left hand, with less strain and less frustration.

As your hand and finger muscles stretch and become stronger and more flexible over time, you can then add the pinky back into the challenge. 
Best of luck, and have fun!

- Lisa