The Firhill side recovered from their heavy 4-1 defeat to Dundee United on League Cup duty in midweek to claim a hard-fought share of the spoils at McDiarmid Park.
Steven MacLean cancelled out Kris Doolan's opener for Thistle and boss Archibald was pleased with the result which keeps the Jags seventh in the table after eight top-flight fixtures.
He said: "It is a good point. The boys are quite disappointed to be honest, they thought they did enough to win it.
"It shows you how far they have come when they are disappointed with a point in Perth, which is a very difficult place to go to.
"They are a well-organised side and they have got a very, very good threat up front. That is the aim, to get as many points on the board as we can until Christmas and then we will look again and see where we are.
"The boys have done really well and we have got to go and build on it.
"We knew we had a tough run of games with St Johnstone, then Hibs then Inverness. It is a hard three games so it was vital that we started on Saturday getting some points on the board.
"All we want to do is try and stay up, that is our priority."
Archibald handed a start to forward Christie Elliott following his decent showing at Tannadice on Wednesday night but was forced to make a change between the sticks as Paul Gallacher made his first competitive start for the club since joining the Jags in the summer.
And the Firhill gaffer was pleased with the veteran shot-stopper's showing after he stepped into side following an injury scare to regular No.1 Scott Fox last week.
Archibald said: "Scott picked up an injury halfway through a training session on Friday.
"We thought at the time that he had broken his metatarsal but after being sent away for an X-ray it proved to be severe bruising. He just wasn't right to play.
"It was good to be able to call upon Paul Gallacher and that was the reason why we decided to go with essentially two first-choice goalkeepers rather than one experienced keeper and another young lad.
"Paul's first touch was a shot low down at his right-hand post and he had a few saves like that including one from Steven MacLean in the second half that came through a crowd of players.
"That's why we brought Paul to the club. He brings experience, he can step into the team and he provides competition for the goalkeeper's jersey."