The winger played the last 30 minutes against Palace, another club he has served on loan.
"I thought I gave them a few problems and I got a free-kick which I thought was a penalty," he told chelseafc.com. Television replays backed up his view.
"It was in the box but the ref said he gave them the benefit of the doubt.
"It was nice coming back to Palace and seeing a few players I know and it is good to be back at Chelsea. Hopefully I will get a look in for the start of the season.
"The double training sessions are getting harder and harder as we go along. I am fit anyway and in a couple more weeks I should be up to a high standard of fitness."