The home side had to wait until the 90th minute to break the deadlock as Lewis Alessandra struck.
"Just after half time they had a little spell where we got a bit sloppy and Luke McCormick's had one or two shots to save, which I didn't really like the look of, but after that I thought we created lots and lots of chances," he told BBC Radio Devon.
"We're just getting on a little run. Clean sheets are a good habit but our problem has been scoring goals, and the pleasing thing is we could've scored three or four."
Plymouth are unbeaten in three league matches.