The striker took his tally for the season to 10 goals but St Johnstone boss Derek McInnes hit out at the forward when he accused him of diving to win a decisive second-half penalty.
But Calderwood believes the forward will have to wait a while longer for his international recall as Scotland boss Craig Levein prepares to name his squad for next month's double header against Liechtenstein and Spain on Thursday morning.
When asked if he thought O'Connor would make it, Calderwood said: "I doubt it but he's heading in the right direction. It's not something we crave.
"I think it will come in the fullness of time but his progression and his attitude since the start of the season has led him to where he is now, and you can see the quality within him."