Xubuntu Reporting False Disk Usage

Hello Guys,
I am new to Ubuntu, I installed Xubuntu to my old desktop PC (to use it as a file/ DLNA server) a few days ago. Main Disk is a 120GB SSD and there are two extra Disks attached to it.
After installing, I copied some important data to my /home/user/Downloads directory, it was something like +/- 70GB of data. Then I put the data to other Disk and deleted the data from Xubuntu SSD. And yes, I did Emptied the Bin. But still Xubutu says that my drive is about 78%/ 82GB used. Why?

root account is disabled as it was since the installation.
all my data is in exteal mounted disks
120GB SSD with Xubuntu installation only has OS data and file, and a few MBs of text, backups of conf files.

Disk Usage Analyzer 2

Disk Usage Analyzer 3