When repairing pipes, how long does it take you to stop worrying about it
leaking or bursting and trust it?

I just finished my first major PEX repair to some old galvanized/copper
pipes that the previous owner cursed on me. One joint is in the attic, one
is in the wall, one is the connection between the spout and the pipe. I'm
worried as heck about it bursting, leaking, that sort of thing, but so far I
haven't seen any indication of a leak.

If it isn't leaking by the first 2 minutes, is it safe to say it ain't gonna
leak?

Is there something I can do to mitigate the danger of having a spout fitting
right next to a 220 v plug? (washing machine hot water tap and the dryer
plug basically) I'm thinking that if the water line bursts, spills water
all over the 220 v outlet, I'm in a serious world of hurt.