Big congratulations.
Did my first solo last Saturday too after about 12 hours.
Had absolutely no idea about it until after 5 circuits my instructor called the tower to announce that we were making a full stop landing this time as opposed to a touch and go as he was getting out!
His last words were "you're going solo mate, one circuit, see you back here" and with that he unplugged his headset, got out and closed the door!
To say I was nervous would be a massive understatement but the feeling afterwards was amazing!