Can Cable get Damaged?

I went to the rear of my set-up just to move some wires over and I noticed that the interconnects from my Rega p3 (standard wires) were extremely folded, curled, bent out of shape and tangled at the pre-amp end near the connectors. I must of been very sloppy when I first hooked up the table. Just wondering if ant damage could occur over this and any idea of how to test for it?

yes they can - mostly if anybody steps on them.
It might be that after straighten things out with your cables they need a certain burn in time again, due to the "new" position of the molecules to each other. Trust your ears - as always!
Good luck!
It can Oxidize at the connectors using Copper and it is suggested that you reterminate every few years.Silver does not I believe.
New position of the mollecules?
Everyone knows that when wires are bent, and not perfectly straight it forces the electrons to go around turns, and believe me they don't like it.
Elmuncy is correct. Depending on the degree of bend in a cable or wire the electron police will erect either a yield or stop sign. Electrons that ignore these signs are immediately taken to jail which is usually in the closest upstream component. Therefore, tight bends and kinks limit current flow and should be avoided.

Of course if you bended and don't threat like childrens
It's highly unlikely that your I/C was at all affected by being tangled up. Current will flow in any pattern, so unless you've actually broken wires or loosened the connection in some other way, you've nothing to worry about.