The under-fire Town boss saw a first home League One win of the season slip through his fingers at the sixth time of asking in dramatic style on Saturday as Swindon netted a late leveller for 3-3.
Shrewsbury, who remain 22nd in the table after just one win from their first 11 games, had led 2-0 and 3-1.
The home side were made to pay for dropping deep late on as Matty Smith fired a deflected equaliser to extend Salop’s run to six league games without a win.
Ricketts, whose side are not involved in midweek action, said: “It’s a natural reaction, a self-defence mechanism, thinking to step back and absorb rather than pushing on and getting pressure higher up the pitch.
“Thinking ‘maybe I won’t step up to put pressure on and I’ll cover behind’, consequently the player in front has to do that and you sink back in.
“It happened because they were so desperate and eager to get over the finish line. We’ll analyse it and work at it so next time we get in front we’ll stay there and see the game out.”
Goals from Aaron Pierre, Matt Millar and Dave Edwards were not enough for a first home win since February.
“I think their belief and confidence is good, they understand there’s an awful lot of good stuff from the two games before and the five we’ve won this season,” Ricketts added.
“We just haven’t won the games in the league which we should have and deserved to. We have to maintain that and make sure we do win those games.”