When using grunge textures, such as in the second graphic, make sure they're not over a person's face.
I refuse to believe that this is the first time you've used photoshop - these are amazing if it really is. Another thing to watch for is glare effects like in the last one. The glare on the faces dulls the appearance and makes them look messier. Try putting it behind them. Also be careful with blending, but that is something that will simply improve over time.
Good luck!
Thanks to the both of you!
I have never had photoshop
but i have used a thing called photoplus
which is basically a dumbed down version of it
But thanks and I will try to look out for those things.