Help me write a short story for my creative writing class on the theme of time travel

As Sarah stepped into the time machine, she felt a chill running down her spine. She had always been fascinated by the idea of travelling through time, but this was the first time she would be doing it for real. The machine whirred to life, and a bright light enveloped her, blinding her for a moment. When the light faded, she found herself standing in the middle of a bustling market square. The sights and sounds were overwhelming, and she struggled to take it all in. Suddenly, she heard someone call out her name. It was her great-great-grandmother, whom she had only ever heard stories about. Sarah approached her cautiously, not wanting to disrupt the delicate balance of time. Her great-great-grandmother greeted her warmly, as if she had been expecting her. They spent the day together, exploring the town and talking about their lives. Sarah was amazed at how similar they were, despite the many years that separated them. As the day drew to a close, Sarah knew she had to go back to her own time. She hugged her great-great-grandmother tightly, tears streaming down her face. But as she stepped back into the time machine, she realized that she had left something behind - a piece of her heart in that long-ago time. Back in her own time, Sarah couldn't stop thinking about her experience. She knew she would never forget the connection she had made with her ancestor. And she also knew that, no matter where or when she went, she would always carry that piece of her heart with her.