I have a suspicion you are running as an Ultrapeer (UP for short.) That means it's not so important for you to be uploading files. What you are doing is giving a small amount of bandwidth for others (leafs) so they can connect more easily. The files you see passing thru on the monitor window are other users downlding/uplding thru you. Running as a UP is very healthy for the network (as long as you're not firewalled.) The more the better.