The Dutch full-back believes that the Welsh side were unlucky to be defeated at home by Tottenham and should have snatched a point after rallying from 2-0 down in the first half
The Capital One Cup winners were undone by two first-half strikes from Jan Vertonghen and Gareth Bale and despite a rousing comeback that saw Michu find the net in the second period, Michael Laudrup's side could not find an equaliser.
"We are a little bit disappointed," Tiendalli told the club's official website.
"I thought we deserved at least a draw. The first 20 minutes wasn’t so good, but we fought for each other throughout and I thought we should have got something in the end.
"Nathan Dyer was very unlucky when he hit the crossbar, but our mentality was very good. We created a couple of good chances through crosses into the box, but it just didn’t fall for us."
The 27-year-old turned out at right back following a calf injury to regular Angel Rangel and the Dutchman went on to speak of his desire to make an impact in the remaining matches of the season, with his current contract set to expire at the end of the season.
"I’m just doing my job," the Dutchman offered.
"I know what I can do and I try to perform well for the team. There are still plenty of games left this season and I want to try and play as much as possible."
The Swans have been shaky since their maiden trophy triumph against Bradford City in late February, taking only one win from their last four league matches.
However, Tiendalli believes the forthcoming trip to relegation-threatened Norwich offers a good opportunity for Laudrup's men to get their season back on track.
"We have been unlucky in the last three games and deserved more points," he added.
"But that’s football, and you don’t always get what you deserve. Every game is tough in this league. Norwich away is a tough game but we trust each other than we can go there and get some points.
"We have a team that is mentally strong. We know we can win, especially at home, and we showed that fight in the second half against Spurs."