Vertonghen impressed in the 1-1 draw.
He said: "It's a dream come true to be in the Premier League. It's a lot harder than when I played in Holland.
"Against a mid-table side, Ajax would win this sort of game - but not against West Brom. Matches are difficult, you must fight until the 96th minute and keep your concentration.
"The tempo is higher. West Brom kept coming, shooting the balls and the challenge of Lukaku was very strong at the end."