WAAAY too big. Save your sigs as .png if there is no animation involved as it preserves transparency and has no quality loss. If you saved this as .png there would be no white around the outer glow.
Not ,much done to it really 2 renders and some blending effects e.g. Outer glow.
This is a great time to start looking at harder tutorials because your starting to find more in Photoshop.So keep up your work and look at some harder tutorials.