McCulloch was at fault for Falkirk’s second goal, with Saturday’s result meaning Rangers slip to third in the Scottish Championship table after Hibs beat Alloa 4-1 at Easter Road to leapfrog the Ibrox side.
And if Rangers remain in third spot after the final game of the season next weekend, they will have to win three two-legged play-off matches to earn their place in the top flight.
All four goals came in the second half with John Baird and Tom Taiwo firing the Bairns into 2-0 lead, before Rangers snatched a point through Haris Vuckic’s header on 83 and Nicky Law’s strike in the fifth minute of stoppage time.
Referring to the booing after Taiwo’s 61st-minute goal, McCall said: “It was very sad, and I was sickened to hear it at the time.
“What did please me was that, after a couple of minutes of it, the supporters then turned it on its head and drowned out the booing with claps. That’s what we need as a club – togetherness.
“It doesn’t matter what has gone on last week, years ago, months ago, today. It’s all about next week and the future. The players will need the supporters as much as the supporters need the players.
“I think we got what we deserved in the end. To be two goals down with the time left and come back to level was pleasing.
“We kept going and showed desire, togetherness and drive. We did not accept defeat and we will need all that next Saturday and also in the play-offs.
“We started the game well but Falkirk scored from a set-play and then on the break. It was looking doom and gloom but we kept at it. We made a lot of opportunities, which I was pleased with but we made a lot of errors as well.
“It’s a blow in terms of the league position but we thought we would have to go to Tynecastle and win. We still have to do that. Obviously, if Falkirk perform like they did today, Hibs will have it hard as well.”
His opposite number at Falkirk, Peter Houston, was unhappy with referee Euan Anderson saying: “We almost had to play until Rangers scored.
“I don’t know where the ref got the injury time from, because he told our players there was 90 seconds to go and we went up the park three times.
“Yes, there were five subs and I think the physio was on once, but anyway I will talk about the positives. And the positives are the performance, the counter-attacking. We could have scored more goals.”
On the final day of the season, next Saturday, Rangers face champions Hearts in Edinburgh while Hibs travel to Scottish Cup finalists Falkirk.