This reminds me...

Ahh, you remind me of so long ago when I was young(er).

Anyhow, this is an excellently written song, only the instruments, let's be blunt, are pretty horrible. Not your fault actually, cos the guitar sample that comes built into LMMS is actually a chord.

Replace your guitar instrument with Presets -> TriOsc -> SEGuitar, and plug it into a channel (let's say, 1). First, however, go to the effects tab on the instrument window, and uncheck the orange lights on Plate and Phaser. Download CamelCrusher, and put it in channel 1, set it to what you want (my personal favorite is Dark Crunch). Attach Calf Reverb onto the channel, set the wet amount higher than the dry amount, and then give it a try. This is one way of making a realistic guitar sound if you don't have a mic.

So pretty much your writing is awesome, but your program is pretty bad, and also you need a little more experience in the music writing world. Solid work, though!