The Saints dominated large parts of the match at Inverness, but it was Caley Thistle who had the clearer chances throughout the 90 minutes. The deadlock, however, remained unbroken with the point moving St Johnstone above Ross County and into fourth in the Clydesdale Bank Premier League table.
"We had two lapses in concentration from balls over the top which could have cost us, but it would have been a travesty if we had not taken a point," said Saints manager Lomas.
"For an away performance, that's about as good as it gets in Inverness because they've given some teams a real hiding here this season.
"Terry Butcher will probably think his side should have nicked it, but I don't think he'll be too pleased with their performance."
The draw extends Caley Thistle's unbeaten run to seven matches and moves them to within two points of second place Motherwell, but manager Butcher knows his side did not play to their usual high standards.
He said: "I'm very disappointed. The back four and the goalkeeper did very well as they had to deal with a lot of pressure.
"St Johnstone had good possession, but didn't really make a lot of clear-cut chances. We had chances, but I was disappointed with us going forward. We can play a lot better."