Normally BB spindles are heat treated to a point where there's very little ductility and they'll break before bending. However, I have seen a few bent BB spindles in my lifetime. It's till more likely that your problem is in the crank or chainring spider.

Here's the definitive test. Figure a way to hold a pencil or other pointer steady at the height of the spindle. For example you could remove the pedal use a figure eight rubber band to hold a pencil on a pump which you hold vertical on the floor. Now turn the crank and watch for spindle movement vs. your reference. If the spindle is true, then the problem is in the crank.

In the future, don't pound away on an unsupported crank arm to remove a cotter. Support the crank arm with a block of wood or a short length of pipe, braced on the ground, so the hammer's energy stays in the cotter, and isn't used to beat up the spindle or bearing.

Sadly, the art of properly and safely removing cotters has gone the way of Damascus Steel, and folks are blaming the bike for the issues resulting from their own ignorance.