The Blues' winger raced onto the end of a much-praised Cesc Fabregas pass for Chelsea's second goal at Turf Moor, but says he can do even better when he is fully fit.
He was taken off by manager Jose Mourinho with 12 minutes to go, and insists he is still adjusting to life back on the pitch after a summer that offered him little chance to wind down.
“I enjoyed the World Cup a lot, so I got out of that with a lot of confidence,” said the German.
“I came back to Chelsea, and obviously had a very short break.
“(At Burnley) I think it was a good start for me, but of course we can be better. And when I am 100% fit, there will be more.
“So there's a lot of work for me, but I'm feeling good. I'm enjoying my game, I'm enjoying being on the pitch.
“I think the whole team played well (at Burnley). We had a lot of control, passes, good combinations. It was a lot of fun on the pitch.”
Chelsea will be looking to continue their good start on Saturday, with the visit to Stamford Bridge of Burnley's fellow newly promoted side Leicester City – who drew their opening match of the season 2-2 with Everton.
Mourinho will, for the first time this campaign, have a full squad to pick from following the return from suspension of midfielder Ramires.