The captain has urged Vern Cotter's side to finish with three wins out of five after beating Ireland and Wales earlier in this year's championship.
"It makes you sick when you watch it back," said flanker Barclay of Saturday's 61-21 loss at Twickenham.
"I'm very confident there'll be a positive reaction from the group."
The Scots last claimed three wins in a Six Nations series in 2006.
"We've been on the right path, certainly been on the right trend for a while now," said Barclay. "I don't think anyone saw that game coming at the weekend.
"We've got one more game left against Italy, which is a huge game now to try and finish the championship on a high, finish the championship with three wins from five and potential to finish second, which we've never done before.
"You can't gloss over it, the stuff that went wrong. We just didn't play well enough and we just made too many errors, couldn't get a foothold in the game, gave away a lot of stupid penalties. I like to think of it as a bump in the road, albeit a fairly big bump at the time."
"Regardless of what happened the week before, you have to go out and try and win the game and that's the case this week. It'll be a hard game; it always is tricky against them. We have to go out and play much better than we did at the weekend.
"[Italy] have played some good stuff in patches in the championship but undoubtedly they'll come to Murrayfield targeting a win.
"The boys are confident. We realise we've got to right a few wrongs."
Captain John Barclay says Scotland's final Six Nations match against Italy is a chance to "right a few wrongs" following their heavy loss to England.