Whoa! Easy there, M8! ;)

It's called a "composite image" and you just made your first! That is a major accomplishment and a major success in and of itself! You made it work! You did magic! Now you know that you can do it AND it's big fun! :)
None of us start at the top, M8! We all start with our very first composite. "The journey of a thousand miles starts with the first step." It's a very good first composite, M8!
The major issue I see with it, which is to be expected in a first composite, is "blending". In other words, the plane looks pasted on to the background. That's pretty reasonable because it IS pasted on to the background, hee, hee!
For me, one of the most challenging aspects of composites is getting the aircraft to blend well with the background so that it appears natural. So, how to approach that problem? Well, start by looking at the image and make note of everything you see which causes the plane to appear separate and discrete from the background!
Some things to routinely look at are:
1) Color or hue.
2) Brightness and contrast.
3) Sharpness, unsharpness and roughness.
4) Inconsistencies in lighting.
Once you have your list, start working on those things. Tweak, tweak, tweak (non-drug type)! Mess around enough and you'll discover things and start to develop a feel for it. There's no way but to use your eyes and try tweaking things! It just takes time, experimentation and experience. ;)
Which editor are you using, M8?