The Bulls struck through Joe Colbeck and Michael Townsend to move clear of the relegation places at the bottom of League Two.
"We had won four out of five and you think you have turned the corner, but we haven't," said Lillis, whose side had levelled through Stewart Drummond.
"We feel we have given away sloppy goals, especially the second one.
"People have players to mark but they didn't do that and it is something we will have to analyse and then work on it in training. Some of our open play was good but some of it fizzled out."
Source: PA
Source: PA