Defender Shane Duffy says Albion shot themselves in the foot by falling behind inside a minute at Leicester yesterday.
The Seagulls lost 2-0 and Duffy said afterwards they cannot keep giving away so many soft goals, after a 2-0 defeat at home to Manchester City the previous week.
He said: "It was disappointing with the start obviously. We put ourselves in a tough position, especially away from home first game.
"The first half we were a bit sluggish I think and the second half we came out a bit better and kept the ball a bit better but a sloppy set piece probably killed the game off.
"We've got a lot to improve on."
Shinji Okazaki tapped home Leicester's opener inside 60 seconds and Duffy said: "We were on the attack and it was sloppy. We worked all week on how they play and it killed the game plan earlydoors. We shot ourselves in the foot and it was an uphill battle from there.
"We dug in first half, stayed in the game up to half-time and there's always a chance of getting back in it but we weren't there today and we've got to improve a lot.
"The (goal from the) corner has killed it and got them in crusie control.
"You can never accept losing, it's difficult but we won't let ourselves get too down. We don't like losing football games but this is a tough place to go. A lot of teams will lose here, it's just all about how we react and bounce back.
"We've got the right people and manager to do that. It's not the start we wanted but it's a long season."
Duffy added the Seagulls cannot keep saying they are learning at the top level and said: "You can't really keep using that it's a learning curve because you'll get caught out. If you looked at the two sides, there wasn't too much in the game.
"They had a little bit of quality up front, maybe that has shone through in the end. I don't think we're a million miles away from that team who won the league two years ago, we're not too far away. We're learning obviously but you can't keep giving soft goals away as in this league you get punished.
"It's completely different to last week where we made them work hard for it but this week we gave it to them too easily. That was the disappointing thing.
"We're obviously frustrated because we feel we can compete at this level and we haven't got off to the start we thought we would.
"It's only two games in and, listen, we're probably going to bring a few players in and strengthen. By the end of the season, we'll be good and it's just taking slow steps at the minute to get used ot it."