The Algerian midfielder was handed a first start at St. James' Park after his loan move from Schalke 04 on Tuesday as Steve Bruce fielded a strong line-up for their fourth round tie against the League One outfit.
In front of a sell-out crowd, Joelinton saw two goals correctly ruled out for offside and require a fourth-round replay at the Kassam Stadium if they are to reach the fifth round of the competition for the first time in 14 years.
Bentaleb told nufc.co.uk: "We're a little bit gutted by the result but, at the end of the day, we managed to not lose. We have a replay where we can show much more quality. We expected a tough game and that's what Oxford brought to the table.
"It's disappointing because we had a lot of chances and knew we could win this game. We had enough chances to kill the game but some days, you have games like this where the ball just doesn't go into the net.
"We knew it wasn't going to be an easy game and we now have to recover, focus on Norwich and after that, we can speak about going to Oxford.
"I think it was important that we didn't concede. We stayed strong defensively to keep a clean sheet but we have to show more in the replay. We know how important it is for the club to get through to the next round and we are willing to work very hard to achieve that."
Despite the result, Bentaleb - who made his professional debut for Tottenham Hotspur in 2013 - expressed his delight in featuring for his new club and praised the home fans for their support during the last 32 clash.
Newcastle's attention returns to Premier League action when they host Norwich City on Saturday and the 25-year-old is determined to register his first win with the Magpies against Daniel Farke's Canaries.
"It was exciting to make my debut in front of this crazy crowd," Bentaleb added. "I've missed this feeling and when I first entered the stadium, I saw this unbelievable atmosphere. It was a special feeling which brought back a lot of memories.
"I always loved playing in England, even when I left. I wanted to come back and now I am back and so pleased to be at a club such as Newcastle with some crazy fans like they have. They pushed us through the game today and, unfortunately, we didn't manage to get the win but we will try to be better next time.
"I haven't played for a long time so I was just focussing and getting ready to rumble. I prepared myself for a long time and I think I need to take it step by step to get back to 100 per cent in terms of my quality.
"We know the game will be very tough. Norwich play good football even though they are bottom of the league. We know they have some good qualities and they can be dangerous at times. We must be at our best and fight for the points.
"We know, deep down, we have the quality ourselves to beat any team in this league. We have seen that in the previous games so we will go into that with the belief that we can get the win."
