They say there are two primal reactions to any situation: fight or flight. Let me suggest a third: holding for a moment, letting God make the decision for you. As fearful as you are, as stressful as the situation might be, God will hold you up. It is a moment I often forget to take, as used as I am to thinking I am in total control of my life (a laughable concept). But a necessary one. As usual, I illustrate in poetry:

Plunge in.
The water’s cold,
so cold it stops your heart
for a moment. And then
you come back into yourself,
all at once, water — wet, breath — held,
eyes — open, to clear blue impossibilities.
You will panic or be at peace;
it doesn’t matter which,
except in terms of long-term survival.
You will swim, after a fashion, or not.
It will be easier if you let your body go,
but that requires a yes you may not be ready for.
Try to say it anyway. The tide will lift you,
even if the yes is a lie.