Gradient tool problems

Was trying to add emphasis to a shadow using the gradient tool in a selection and this started happening. I've restarted PS, restarted my computer, and tried a different image all to no avail.

When I click on the gradient tool, most of the options are missing but appear when I mouse over them. They respond as expected when clicked and then disappear if you click another tool and go back to them.

Also, once a gradient area is created there's no way to actually apply any changes to the image.