The Alex were sent down by local rivals Port Vale as they suffered their sixth successive defeat.
"It's horrible, I certainly won't want this feeling again," Garratt, 21, told BBC Radio Stoke.
"It's sunk in now, we just have to try to move on and restore some pride."
Crewe's 3-0 defeat by Vale sealed their fate, leaving them 16 points adrift of safety, but boss Steve Davis is already optimistic about their chances of bouncing straight back next season.
Garratt is also bullish about the prospect but knows a lot of work needs to be done before they finish the current campaign.
"If anything, we've got to work harder to get some results," he said. "We don't want to let the season fizzle out, we want try to put a smile back on some faces.
"We want to come back at the first attempt and everyone's determined to do so."
Despite returning to League Two four years after winning promotion, Garratt is one of a number of the Alex's younger players hoping the setback will benefit them in the long run.
"I've played a lot of games in League One, it's been great," said Garratt who has made 106 appearances - 98 of them in the league.
"Obviously I would've liked a lot more positive results and positive seasons.
"It doesn't feel like it at the moment but in years to come, when you look back on it, it might have made you a stronger player and it's an experience that helped the younger players."
Goalkeeper Ben Garratt says the Crewe Alexandra players are determined to "put a smile back on some faces" over the final five games of the season following relegation to League Two.