You are pretty underleveled, but it's perfectly doable still. If you're doing ok until Yuna gets smashed, consider buying a ton of softs from O'aka and customize everyone's armor. You need 30 softs to add the Stoneward ability. Spam aeons and win forever!

This is one of the best places to grind in the game though so if you plan on grinding eventually to catch up this is the time! The enemies in this area give good AP relative to where you are in the game, you're sandwiched between two save points, and O'aka is there to help you restock. You can always just pick off one enemy and then escape for a small amount of AP until you can handle the whole mob :v