FPS Problems

So recently I've been getting terrible FPS and just low FPS in general, a week ago I was getting about 20-30 now its about 5-10 if any one has any solutions please! I need help  

http://optifine.net/downloads.php

Download the latest version, run it and install it. After it's done, open up minecraft and switch your profile to the newly created optifine profile. That's it, you should now have better fps now.

To configure Optifine to get even bigger FPS boost, please refer to this guide. http://sgtekkit.net/threads/tutorial-mostly-pictures-configuring-optifine-to-combat-lag.8319/ If you have any other questions, let me know.

Just FYI, Optifine works for a lot of people, but it has never done anything at all to my FPS. Just wanted to say that, it's worth a try, but it's possible it won't do much.