There are nights when it’s not good to catch Jason Terry, and Wednesday night was one of those nights. The Celtics guard had a miserable night against the New Orleans Hornets: 0-for-5 shooting, zero points in 20 minutes, a couple of missed opportunities to seal a win. The Celtics lost, of course, 87-86, perhaps their worst defeat of the season. If they complain about their playoff seed, they can look back at getting swept by the Hornets as one of the primary reasons for it. Terry took the loss personally, and he is moody after tough defeats, especially when he feels he could have done more. The Celtics acquired a team leader when they signed Terry to a three-year deal last July, but they also took on a player known for his highs and lows, his rainbow 3-pointers, his “jet plane” soaring motions down the court, and his endless chatter. There are moments, however, when Terry, at age 35, grows angry — perhaps because he can’t drop those threes the way he used to or can’t stop the dribble penetration of younger, quicker guards. It’s a harsh reality for an aging player, and Terry relayed that Wednesday night. “I’m about to get more aggressive,” he promised. “I already know what time it is. Any time you have a game like I had tonight, it’s time to turn up the aggression level. “I can’t wait until the third or fourth quarter and think I’m just going to get it going. So that’s my responsibility. The team is counting on me. And I told them, ‘This one’s on me,’ so I’ll definitely make up for it Friday.”