can download but no one can upload, why? mac osx

[pandemic]

Hello
Am new to limewire but have been able to download music for a week or so just fine-ish, although last few days have seen 'need more sources' alot....
But when i check my uploads at the bottom of the screen and in the library to see how many uploads i have there are none. (am assuming Hits are not the same a uploads as i have many hits!)
have also unchecked automatically clear completed uploads in prefrences.

I have looked at many threads and think i have check and uncheck what needs must.
At the bottom of the screen it does say i am sharing 700 odd songs,
am i sharing and dont know it?
The connection must be working ok if i can download...right?

Would be very gratefull for any adive.
What on earth am i missing or doing wrong?

Some info
I have a mac book pro osx, version 10.4.6
memory 1GB, processor 2.16 ghz
Am connected via modem through talktalk (heard they have problems with limewire?)
i do have a brickwall in front of the globe... but my 'connection to the network is very strog apparently.
Im with leaf...dont know what that means.

do helps.