painting my bathroom tiles
Shower tiles, wall tiles, or floor tiles?
I considered the same route and ended up not doing it. From my research if it is shower or floor tiles, don't even go there. Paint won't last and will most likely end up looking worse that what you currently have.
If it is wall tiles outside the shower you might have a chance with the proper prep work, the right primer and a high quality paint or epoxy from a real paint store (not the big box stores), but it will still look like painted tile.