In addition to Randy's excellent answer, you can consider a similar expression which you will probably hear at some point.
"I am in a bit of a bind" means that you have a difficulty and must decide between choices.
Another way of expressing the same idea is this:
"I am caught between a Rock and a Hard Place".
BIND itself, may be visualized in association with Ropes, since to be "bound" means literally to be tied up with ropes. If you were captured and made a slave, you would probably have your hands "bound" with ropes, and you might also have a rope tied around your neck.
This is "Binding".
So if you are in a Bind, you feel "Tied-Up".
Any time you have a difficult decision to make, you can say; "I am in a bind."