Image made in Photoshop looks blurry and pixelated

I made this in photoshop and as you can see, it looks blurry and pixelated. I have tried to sharpen edges and all sort of things, but nothing seems to work. When I make a standard edge it doesn't seem to fill the edge completely but instead fills some of the pixels 100 % and some more like 40 %. I am making designs for a webpage and using mockingbot to design before making it in photoshop. Everything i make in the mockingbot is 100 % sharp and my photoshop photo just looks terrible compared to that.
Does anyone know, what I am doing wrong? I am new to photoshop so any advice is very welcome
J
