Stephen Myler admitted he was unaware of the rules when he mistakenly kicked the ball into touch during last week's Aviva Premiership final at Twickenham.
With just seconds remaining before half-time, the Northampton player kicked the ball straight into touch and expected the referee to blow up immediately to signal the end of the first 40 minutes.
Instead, referee Wayne Barnes awarded opponents Leicester a scrum because the ball had not bounced its way over the line.
Myler said: "There was a massive confusion in interpretation from our point of view, through speaking to the referee, about what we could and could not do.
"In another situation in the past I have kicked it out on the full from the half-way line and the game ended. That is what we had in our heads and why we were in a state of shock."
Following the scrum, Northampton conceded a penalty and Leicester increased their lead to 11 points while the Saints were reduced to 14-men when Dylan Hartley was sent off for being abusive to Barnes over the incident.
Hartley subsequently got an 11-week ban and missed the Lions tour while Myler - who is currently on tour with England in the Americas - has learned his lesson.
He added: "Individual errors are going to happen. We are human but if we can learn we can continue to do positive things in the future.
"I'll not be doing it again when I pull on an England shirt (for the first time) on Sunday."
England face Uruguay at the Toccurshe Charrua Stadium in Montevideo over the weekend.