"But, in football, you never know what is around the corner. "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."
The 28-year-old Stewart, who was appointed club captain at the start of the season, returned for a second spell at the club just over two years ago.
"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," he told Hearts' website. "But it's an industry that can change very quickly."
Hearts captain defended his side, who finished third last season but have won just two of their six Scottish Premier League games this term.
"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," said Stewart. "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 set-up on Thursday, when Scotland manager 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 Accies, 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.