Hey I've been playing for quite some time now say a year or so and at first I started creating like hard metal and metal riff's and some acoustic chord riff's and sweeping stuff but then I wanted to make something serious and like a ballad.
Lets take as an example Dance of Death by Iron Maiden. their lead intro riff sounds very melodic and also a bit medieval. So, I tried to actually make something like that; you know fiddle with some chords and try to layer a medieval sounding melody over it. But, it started to get worse and worse the more I tried.

Anyone got any tips, anything really like what scale I should use more or the do's and don'ts or something..
Anything would be appreciated.

rhythm of the melody is very important. listen to lots of battle metal and the like, and learn those style songs. Explore the chords you use, and pick out notes from the chords and then try and say words through the guitar.

so if i want to write a blues ballad style song, i'll think of the words i wanna say and then try and make the guitar sing them.

You have gotta force yourself into playing like this or leave it a week and the go back to the guitar. You must avoid frustration at any cost or you can risk losing your love of the instrument.
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Try minor scales and modes for more exotic sounding try a harmonic minor scale
George Bernard Shaw

Hell is full of musical amateurs.
Think of melody that sounds like what you want. Now figure that out by ear. Success! I make that sound easy -- it's really pretty difficult. If you can't even think of melody that sounds like what you want, try listening to more songs of that style and learning along the way.