hmm..
I dunno... I like what you have here. I know this is one of your first compositions and it shows. I would suggest making a bit longer and make sure the melody doesn't stray off in the middle of the song (which it did). Here's an idea: apply the sonata format. In case you don't know, this is the sonata format:
A ("exposition"): Statement of the first theme, transition into a second theme which is in a different key (if the first theme is minor, the second theme is the major key of that minor (ex. C minor to C major)), same transition melody. Repeat.
B ("development"): Anything goes. For this part, I recommend variations of the first theme. That way, it sticks out more in the listener's mind
A' ("recapitulation"): Big restatement of A, except both themes are in the same key now.
Yeah this format is very classical-y but apply it to your music and see how it works. It works for me. If you have any questions, don't be a stranger and ask. My door is always open :)