ouch.

A good try here, but a bit painful to hear.

The loop is sharp, Very sharp on the ears. I would pull the tone down an octave personally. The sound also has a brief stop before it loops, may want to clean that one up. I would love to hear this one refined.

And as for how short it is, loops don't need to be long to be good.

I look forward to seeing your skill improve. The beat is good, and the structure is good. Only tone down the lead instrument, maybe drop it's volume a little, to let the other instrument breath so to speak.