Honestly? The great plateau is one of the most difficult parts of the game. Once you have some good clothes and regain some heart containers you'll feel a lot better. Don't be afraid to take things slow starting off and approach situations strategically, or even avoid combat if you can.

My one tip would be to try flurry rushing! You just have to dodge (side hop or backflip) with good timing and it will often do some good damage and knock that monster down at least.