Thanks, I am hoping for something to correct the unevenness of the existing stain first.
What kind of stain is it? Is it an acid stain or a water-based stain? Something to be aware of is that stained concrete is not going to have an even or solid colored type of look. Because the porosity and density of the surface changes throughout, so does the way the stain takes. If it's an acid stain, the amount of free lime and other minerals that are prevalent at the surface controls what the stain looks like as well. Unevenness is the typical character of concrete stains and why most want them.
It does not sound like it is sealed, so you can go back with the same product and reapply it. If you wet the surface, you will get an idea of what the surface will look like once you apply a sealer. The surface will darken and the colors will pop.
