The first win in London since 1983 appears to have been a tight affair on the scoreboard but the Scots enjoyed the bulk of the possession and territory and shows they are maturing and growing in confidence, according to the Glasgow lock.
The 24-year-old said: "Maybe a year or two ago, when things went wrong, we might have gone downhill from that.
"I think we have learned that things are going to go wrong in a game and you have just got to react to that, adapt and bounce back.
"I think we did that really well today. Things didn't go our way at certain times and they were putting pressure on us but we stuck to our systems and what we wanted to do."
Next up for Scotland are Wales at Murrayfield when the challenge will be back up their fine win over England.
Cummings added: "Obviously coming down here and winning for the first time in 38 years is a massive occasion for us and we will look to push on from this. We definitely feel like we are building something. There are still areas for us to improve - we aren't perfect and we know that."