if i notice in the connections tab that someone is downloading all of my music files should i be worried? also i browsed their shared files and it is all from me. is this bad?

Not if you don't mind sharing your music. If it annoys you that one person should be downlding so much from you then limit how many files they can downld at one time. Tools>Options>Uploads>Slots & change the no. of files a person can downld from you at one time.

So they are not freeloading then at least. Let's hope that person maintains those files to be shared. Hate to think they might be a leecher. It could be a new user with not much to share. Many people start off that way. Then bit by bit increase their share quantity as they downld it from others.

Generally speaking it's good to have people uplding from you b/c it enables you to get better search & downld results.