Leigh Griffiths was denied what would have been the matchwinner when his 78th-minute free-kick crashed off the underside off the bar and crossed the line but was not given by referee Euan Norris or his assistant.
"From where I was, it was difficult to see," Locke said.
"I've just seen it again and obviously it's in but the referee didn't give it and that's the most important thing. There is no point in me sitting here worrying about it.
"It was a great strike and it went over the line and it's one we've got away with so maybe the luck is turning for us now."
Former Dundee United boss Peter Houston has been linked with the vacant manager's position ahead of next weekend's Scottish Communities League Cup final but Locke insisted his focus was solely on preparing the players for the showdown against St Mirren.
Locke added: "I know Housty' well, he was the youth coach when I played here so we go back a long way.
"But, until we are told anything differently, we will just carry on.
"If they bring somebody new in, then great. If not, we'll just prepare the team as normal for the next game."