The Toon won 2-0 thanks to goals from Sandro Tonali and Bruno Guimaraes, with Nicolas Jackson seeing red for the visitors in the first-half.
Howe said afterwards: "I thought first half we were really, really good. I was very pleased. The sending off changed the game.
"With the score line as it was, it was a tricky second half for us us mentally because we wanted to go and attack. That was the message. But on the pitch I think it felt different, Chelsea tweaked things to make it difficult for us. But we hung in there and did well mentally in the second half.
"I probably enjoyed the first half more than the second. The second half was stressful, we were making changes. We started in the way we did and looked really comfortable until they tweaked things.
"With the scoreline, they had nothing to lose at that point. I was pleased with how we defended and Nick (Pope) made two excellent saves - you can't forget the part he played today.
"But we got over the line and that's the major thing in a game like today."
Jackson deserved his red
On Jackson's red card, Howe said: "It was a big moment. For me, it was a red card but I haven't seen it again, I'm going with my initial reaction.
"I'm sure he hasn't meant to elbow the way he has but it doesn't look great."
The Toon manager was also keen to highlight the influence of the home support on the win in the Sunday sunshine.
He added: "The way we play has to fit the culture of the club and what the supporters want. The supporters here want fast, aggressive, attacking football. They want their team always wanting to score - that's perfect for me.
"I love to try and give them want they want. The atmosphere today was amazing, it was everything we hoped it would be."