North End twice had to come from behind to earn a 2-2 draw with Middlesbrough, meaning they have only lost once in seven home games.
Parry told the club's official website: "We started the game poorly again which is something we've got to put right.
"We can't keep conceding a goal and making it hard for ourselves. If we can get that right and start taking games to people it will be better for us.
"You can't afford to drop too many points at home if you're going to get anything in this league."