The visitors were undone in the dying moments of the match by an Iain Vigurs goal after Michael Ngoo and Jamie Walker had turned the match in favour of Hearts following Rocco Quinn's opener.
McGlynn said: "County put us under pressure right to the end but I felt we merited all three points. Two points have slipped away but I've got to be positive, it was another very good performance from us.
"We played some great football. I thought County scored against the run of play and we had chances to go in front before that.
"We showed character, I always thought we would get back into the game because we were playing well enough.
McGlynn praised on loan striker Ngoo, who took his tally to two in three games with an impressive effort.
"It was a great individual goal from Michael. I thought we were well on top and we got another goal when Jamie Walker put us 2-1 in front," McGlynn added.
"We had chances to go 3-1 up that would probably have killed County off but unfortunately we weren't able to defend right to the end."