FiRsT oF aLl... tHiS tRaCk iS sOoOoO sHoRt My GoOoOoOdNeSs
haha jk
On a more serious note,
So, a few things here. Try to make the notes flow a little bit better together, It almost sounds like notes were put onto a midi sheet, in half/whole/quarter notes and sorta just left there. Maybe there are some note overlaps where I wouldn't put them. I like how you drew out those few notes at around 5 seconds. I'm not sure where you're going with this, i.e. what genre you're aiming at, but try to build a chord progression and layer notes over than progression to make it flow better.
A little EQ goes a long way in creating a better sound, layered with some reverb, test out some effects on the instruments to liven it up a bit! Creating dynamic notes, i.e. not having all notes sound exactly the same, making some of them softer, and some louder, creating glissandos and crescendos is a great way to spice up your composition!
Keep at it!