The England age-group international left Milton Keynes at the weekend having won gold in both the doubles and the mixed doubles.
Agathangelou, a nominee for the CI Cherry Godfrey Rising Star award later this month, and partner Peter Mills were in cruise control in the opening rounds of the mixed doubles.
They had to dig deep in the semi-final however, coming from a set down to beat Gabby White and Jamie Bosnells 13-15, 15-2, 15-2.
The pair went on to win the final beating Frankie Eldelman and Miles McBain, 15-6, 15-5.
There was no time to bask in glory, however, as Agathangelou was thrust straight in to the doubles with partner Vicky Ingram.
The pair stormed to the semi-final without losing a set, where they met Rachael Priddy and Helen Calverly and won 15-7, 15-15 to book their place in the final.
The girls were now in confident mood and outplayed number two seeds Laura Cousins and Sam Ward in the final winning 15-9, 15-10.
Agathangelou was knocked out of the singles by the No 1 seed in the first round.
