After a five-match winless run in the league which saw Newcastle drop out of the top four, they have roared back into contention with five wins in a row.
The run began with a 2-1 home win over Wolverhampton Wanderers which was followed by a 2-0 victory over fellow Champions League chasers Manchester United.
Newcastle are third in the Premier League standings with 56 points from 29 games, three clear of fifth-placed Tottenham Hotspur who have played a game more. Newcastle visit Aston Villa on Saturday.
"I think there's a growing belief that we're getting back to our best form after a difficult period around January time, where we were a little bit frustrated with ourselves in the Premier League," Howe told reporters.
"I think the Wolves win was a big, big moment for us, it got us back to winning ways. We've backed that up with three really tough games over the last week. That was a big test for us mentally and physically, we came through it.
"Now we go into what I see as the last set of games this season, but a big test to come, nothing's decided and we've got it all to prove "
Howe praised Villa boss Unai Emery, who has led the club's revival, with the Spaniard pulling them out of a relegation battle since his appointment.
Villa are in sublime form, winning six of their last seven matches to move up to sixth and close in on European football next season.
"He (Emery) has got a clear philosophy. They very rarely change what they do and tactically they're interesting," Howe said.
"They're going to be a tough challenge for us and we're going to have to get certain parts of our defensive structures right or they will give us big problems.
"Their run is a good one and at home they've been good, so it's another tough away game for us."
The Newcastle boss said injured winger Allan Saint-Maximin will not play this weekend but midfielder Miguel Almiron is "ahead of schedule" and could return to action soon.
