Caley Thistle were on course for their after a strike from Billy McKay but they were denied all three points when David Robertson snatched an equaliser in the second minute of injury time.
Andrew Shinnie also missed a penalty for Inverness as the hosts were hosts were denied a fourth straight victory.
Butcher was disappointed his side failed to close out the match but was pleased with their overall performance.
He said: "I felt that we had done enough to have won the game. We should have won and we deserved to win.
"However, one long ball forward into our 18 yard box and we didn't deal with it properly. But St Johnstone are a good, strong side, who are hard to break down.
"I'm delighted with the way the players performed and it shows how far we've come when we're disappointed to have drawn against a side that have won five on the bounce in the SPL."