Jermain Defoe fired Spurs in front 69 minutes into the match at St Andrews but a stoppage time goal from Liam Ridgewell earned the home side a share of the spoils.
"I felt we had control throughout," Redknapp told Sky Sports after the match.
"We got one up and we just had to continue playing the way we were.
"It didn't last though and into injury time we lost concentration and it cost us. We didn't react and it was poor defending.
"I always felt we had control of the game and were the better team. I thought it was a terrific away performance today, so I didn't really see us in any danger.
"Up until the end we had been top class, but that's how it goes. I couldn't complain about the effort and the way we played today.
"I thought we passed the ball well on a difficult pitch and were always in control.
"It was definitely two points dropped."