The New Zealand-born wing's try on his debut saw Scotland take a 10th-minute lead, but a first win at Twickenham in 30 years proved beyond the visitors as England lifted the Calcutta Cup with a 38-18 triumph.
"You can't be negative," said the 24-year-old, who qualifies for Scotland through his paternal grandparents. "You've got to be positive. There were heaps of positives: scoring tries and staying in the game."
He added: "But you've got to look at the things you need to work on. There are a lot of things that we need to work on, let's be honest.
"It's just a shame we didn't do the jersey justice; all the boys are very disappointed."
England, bidding to show their December defeat of world champions New Zealand was not a one-off, demonstrated moments of class, while Scotland's few instances of quality were all too fleeting.
Maitland and his back-three colleagues Tim Visser and Stuart Hogg, who was influential in Maitland's try and scored Scotland's second late on, were peripheral figures as England dominated for much of the match.
"Things have gone really fast for me," said Maitland, as he reflected on his Test debut. "I've only been here for a couple of months. To be playing Test rugby for Scotland is a dream come true.
"It's just the start, hopefully, for me. Going back home to Murrayfield is going to be special. Hopefully I get to play and experience Murrayfield for the first time.
"I've still got a lot to prove to the people of Scotland, getting selected having not been in the country for long."