The meeting with the reigning European champions promises to pose the biggest test yet to Tottenham's continental credentials, with Harry Redknapp's men having already taken four points off Werder Bremen and FC Twente.
A double-header with Inter will give them a greater indication as to where they stand in Europe's pecking order, with the Serie A giants brimming with world-class talent.
Gomes accepts that Spurs will need to be on top of their game to take anything from Rafael Benitez's side, but insists they should not be overawed by the challenge in front of them.
He said: "We're not worried about going there and playing them. We need to believe in ourselves and need to keep going like in our last two Champions League games.
"Wednesday will be such a hard game because it's away from home, and Inter Milan are great opponents, but we go there full of confidence.
"We need to be concentrated, need to go step by step. Milan will be the first real big test."
Gomes knows what it takes to make inroads in the Champions League, having reached the semi-finals with PSV Eindhoven in 2005.
He believes the current Spurs squad is stronger than that side, though, and is confident of making similar progress this time around.
He added: "That time we had 12-13 players and here, we have two teams. If you put our second team on the pitch they would do the same job."
Gomes has also played down fears that Tottenham may struggle to break Inter down in midweek with influential playmaker Rafael van der Vaart suspended and England ace Jermain Defoe injured.
He said: "We have quality strikers. We have a lot of guys who can score or win a match, and Gareth Bale is on fire."