The Grecians had to play over half of the match a man light after veteran striker Jamie Cureton was sent off. The 37-year-old was shown a red card for needlessly kicking out at Anthony Stewart in the 40th minute and Wycombe then blew a great chance to take the lead when Joel Grant's weak penalty was stopped by Artur Krysiak.
The visitors eventually snatched the points when Jordan Archer parried John O'Flynn's low shot only for 17-year-old Kortney Hause to dribble into his own net to move the within two points of the play-offs.
Tisdale said: "It was a fantastic performance from us and it's a mad game, football.
"We were hugely disappointed on Saturday with a 98th equaliser going against us, but we feel great again because that was a great result and a top performance.
"I didn't see what happened for the sending off as clearly as I would have liked to have done but I believe that Jamie kicked out at him.
"If he did do that then he deserved his red card and I can't complain about it, so if the officials saw him doing it, it was the correct decision.
"For our winner Alan Gow produced a brilliant bit of skill and John O'Flynn's ability to keep the ball hard and low was some shot.
"What stood out today was that the nine remaining outfield players gave absolutely everything and no-one flagged towards the end or lost pace with the game."