"I'm teetering on the edge!"
A lot of people have a nagging sense that they are teetering on the edge and that all it will take is one more assignment to send them plummeting into chaos.
If you feel this way, remember that, while it may seem that you are about to go over the edge, you haven't. The thing to deal with is your nagging sense. You are choosing to have negative thoughts that nag you. Perhaps you could employ cognitive behavioral therapy (CBT) techniques to jump out of that pattern by thinking, "I'm doing a good job; I'm keeping my cool and balance in spite of the risk of going over the edge."
So shift your mental picture from one of you trembling on the precipice to you confidently walking along the edge, filled with the promise of discovery. Yes, that's you, on your way to great new things. Enjoy the view!