How can I fix my iPod Touch screen?

I used to listen to my iPod Touch 2g in the shower, by placing it upon the windowsill. But then I noticed it had suffered from water damage, the screen had dark coloured 'bubbles' all over it. To try to dry it out, I run a hot hair dryer above it for a few minutes, then I placed the iPod Touch in rice inside a air-tight container for a couple of weeks. I took it out, but now there are these strange, very faded white clusters on blurry dots on the screen; which seem like it's underneath it, how can I fix this without purchasing a new iPod or iPod components, since I currently cannot afford it.