Everything that i eat or drink except water has a bitter taste this started a few days ago. i gargled with listerine and salt water. i brushed my tongue. i ate a piece of pie and it tasted bitter.

This : This is rather interesting. I would guess that this represents some reflux esophagitis symtoms. You might want to try some antacids to see if this helps over the next couple of days.

Time: There are many different reasons for this and most will pass with time with no consequence. If it continues, a good medical work-up would be suggested to rule out the things that do have a consequence such as acid reflux disease or mercury.