Midfielder Stewart, who was appointed club captain at the start of the season, insists he is happy at Hearts but revealed there needs to be "a fair bit of discussion" before he makes a decision about his future.
The 28-year-old, who returned for a second spell at the club just over two years ago, said: "I'm enjoying my time at Hearts and I enjoy working with the manager.
"And I think anybody will tell you that when you're working with a guy that you've got so much respect for, and you're coming to work and you're learning things and you're progressing, then that's something that you're not going to want to throw away willy-nilly.
"But in football you never know what is around the corner.
"It's an industry that can change very quickly and before I decide what's going to happen, or before the club decide what's going to happen, there needs to be a fair bit of discussion."
Stewart also rounded on Hearts' critics today, telling them they needed "a reality check".
After finishing third last season, the Jambos have won just two of their six Clydesdale Bank Premier League games this term.
Stewart told HeartsTV: "We've lost three late goals that have denied us four points, not just late goals, we're talking last kick of the ball type stuff.
"When you've not got the points, confidence is naturally not going to be free-flowing.
"So it's a case of getting the points first and, with that, confidence comes, and then you can look to rectify the performance side of things.
"It's not as if it's been pathetic. People need to take a reality check at times.
"The expectations can sometimes be a bit stupid."
Stewart is not expecting a recall to the international arena on Thursday when Scotland boss George Burley names his squad for next month's friendly in Japan.
"It's not something that I spend a lot of time thinking about. If it happens, it happens," said Stewart, whose four caps have been spread over a six-year period.
"I'll be delighted if it does.
"If not, it's not something that I'm going to get too hung up on or worry about."
Meanwhile, Hearts are set to welcome back Ruben Palazuelos, Lee Wallace and Gary Glen for this weekend's trip to St Mirren.
All three missed Saturday's 2-1 win over Hamilton, Palazuelos with a stomach bug and Wallace and Glen with respective hip and knee problems.
Manager Csaba Laszlo is confident the latter pair will have recovered in time for the game at St Mirren Park, while Palazuelos says he is almost over his illness.
"I didn't feel well at all on Saturday and there was little else I could do other than go home to rest," he said.
"I am feeling much better now, although still a little bit tired. Hopefully, I will have my full energy back in the next day or so.
"Obviously I was disappointed to miss the game but I think I will be okay for this weekend."