Karl Hawley had fired the Cobblers into an early lead, before the home side secured a share of the spoils through Leon McSweeney's 75th minute leveller.
"I was disappointed that we didn't take the three points having got our noses in front and I probably look at it as two points dropped," Gray said.
"I thought we scored an excellent goal but after that we gave the ball away a bit too cheaply and we didn't really pose enough of a threat ourselves on the counter attack.
"Everybody put in a good shift though and we were hard to break down but we just didn't hurt them enough in the final third."