My suggestion
I'm sure most of us who use clipless pedals have fallen a time or two; it's sort of a right of passage. My right leg still bears the scars of my first fall!
If you're that nervous, though, I would suggest practicing in parking lots or riding bike trails and other low-traffic areas before hitting busy roads again. And make sure that the tension on your pedals is pretty loose. Not so loose that you can clip out inadvertently, but loose enough that it doesn't take much effort to unclip. Beyond that, just make it a habit to unclip one foot (preferably, the same foot each time) as you approach a stop sign/light. I promise it will soon become second nature to you to use them.
Live with intention. Walk to the edge. Listen hard. Practice wellness. Play with abandon. Laugh. Choose with no regret. Continue to learn. Appreciate your friends. Do what you love. Live as if this is all there is.
--Mary Anne Radmacher