Purchased Section of iTunes .....

Question

In the Purchased section of my iTunes account i notice that there is a "Not on this computer" tab with the list of purchased music blank except for the sentence " All your available music has been downloaded to this computer". I wonder why everytime i visit the purchased page it always shows the list of purchases that i made, but this time it shows me the section in which i could view a download from another computer. I have had a problem with a hacker who (while i was using my account) would try to download my music onto their computer but a message was prompted and told me that "automatic downloads had to be done from THIS (meaning my computer for it to happen) computer". Another message popped up saying "my iCloud session has expired" and to type in a password. Also, everytime i log in i always see the message "verify your payment by clicking ok". Someone is trying to shop on my account and because i used up all my money they can't do it but i seem to keep getting the message because of it. This looks very shady. It seems as if the hacker is trying to download my purchases on their computer and that is why it went blank but i looked at the authorized computer and device section of "Account" and their device is not there.
My questions are:
1) How can i find out if the unauthorized user actually did download my stuff ( i believe they did, i just want serial numbers and iDs to prove it) and are there records of this even though they removed their device from the list of devices after they downloaded my media content?
2) Will this prevent me from being able to redownload my songs in the future to other devices other than my ipod and can the person actually listen to it, even though i don't  see their device authorized?
3) When i put more money on my card, will future purchases be put on hold for the purchases that the hacker was trying to make ?

Answer 1

It looks like at some point in history, iTunes created a new 'Purchased' playlist.
This playlist is a special one, but behaves like a normal playlist.
You can add your previous purchases to it.
Another way is to create a new Smart Playlist and set as rule:
Kind - contains - protected
That playlist will always be up-to-date and contains all your purchases.
Hope this helps.
M