iPhone was in my pocket and my pants got wet...now the screen is very dim

If the iPhone is not working properly, the "protective covering" wasn't too effective. Some users dried thier wet iPhones successfully by putting the iPhone in a bag of dry rice, and leaving it alone for several days. The damage you described is not covered by the AppleCare warranty.

Another alternative is silica gel pacs which may be a more effective drying agent. Turn the phone off and leave the phone in a sealed bag with the gel pacs or rice for at least 5 days before tying it again. Never use direct heat such as a hair dryer.

http://silicagelpackets.com/?gclid=CLmrofnk75wCFQO2sgodJyQFjw

If this doesn't fix it, Apple will replace your out of warranty iPhone (including water damaged phones) for $199.

http://www.apple.com/support/iphone/service/faq/#warranty7

Also, there are 3rd party iPhone repair services which may be cheaper. Google is your friend to find these.