Graham Alexander accused referee Bobby Madden of being swayed by St Mirren as he was denied a winning start to his Motherwell reign by Jamie McGrath's late penalty.
Devante Cole gave Stephen Robinson's successor the perfect start as he fired Well ahead at the break.
But the Steelmen could not hang on for what would have been their first win in 11 games after Buddies frontman Lee Erwin won his side a spot-kick with 12 minutes remaining.
Bevis Mugabi was penalised for the challenge on the Saints striker – but Alexander insists it was a soft award and claimed Madden had been "influenced" by repeat claims for fouls coming from the Paisley camp.
"I think we've been harshly dealt with at the penalty," said the former Scotland defender.
"I thought it was coming a little bit because there was an influence, I felt. There was a lot of noise on virtually every challenge – and I mean every challenge.
"I've seen it back and it's a limited touch, if any at all. I feel for the guys in there because I don't feel they deserved to score against us.
"I think it was Bevis (who was penalised) but honestly, I've watched it back and you can hardly see anything.
"I don't know where the noise was coming from but there seemed to be a lot on every challenge. Listen, I know it goes on and I understand it.
"I have to be honest, I felt it was coming a little bit if there was going to be one around the box. It seemed that there was a lot of pressure.
"I am not going to talk about the referee. He managed the game well and did what he could. They have a split decision to make but as a very experienced manager who has been in the game a long time you can feel these things coming."
But St Mirren manager Jim Goodwin reckons Madden got the penalty decision spot on.
Asked about Alexander's noise complaint, the Irishman replied: "Does he mean me?
"Bobby Madden is a top referee, hence he was chosen for the Old Firm a couple of weeks ago. In my opinion, he's one of the best in the country. I thought he had a decent game.
"If he hasn't made the right decision on this occasion, I'm sure he will be the first one to hold his hands up.
"I certainly felt Lee Erwin had himself between the ball and the defender. It sounded like the defender kicked through the back of his calf. You could hear the boot making contact. At the time, I thought it was a penalty."
The point does move Motherwell out of the bottom two and the new Fir Park boss is confident he can steer them away from trouble.
Alexander – sacked by Salford back in October with his unbeaten side just five games into the new season – said: "It was brilliant to be back out there but then you get the anguish of conceding too.
"But there is a lot for us to take on. We need to improve in a couple of positions but there is a group here that can win games."