Identify song and Track upload

I'm trying to retrieve the album name, song title and artist from an audio file using the JEN java library, I have a few questions and issues.

1. Currently I'm using upload track to identify the audio file but it seems to be taking quite a long time(2-3 minutes). How long should this process usually take?

2.I frequently get this error returned "(3) 3|You are limited to 20 accesses every minute." even though I have only made 1 call within 1 minute, why does this happen?

1. What is the difference between song identify and track upload I cant find any JEN examples for song identify where should I be looking for this information?

Thanks