I'm new to the web designing stuff, so I bought a template. I want to change some text in my header. It is saved as a png image. I opened the PSD file in photoshop and changed the text.
I then moved that layer to a new file and saved it as a transparent file.
The resulting file is not displayed at the same size in my webpage. In the webpage, i have the image size set, but still the same result
Template(chainging text on top) 
Photoshop file (see proportions)

Resulting website 
What is causing this problem. Like I said, I took the text layer and put it in its own document where I could save it as transparent