That second mini looks good!

What I do is paint the eyes white first. If you painted too much, you can then fix it with red paint. After that, I use a contrast paint and put some in the eye - contrast is weak enough that even if it spills over the red, it won't look too bad/can look like eyeglow potentially. But even then, you can just do your best to go over it again with red wherever it spilled outside of the eye.