I saw this movie a while ago, perhaps during the 90's. It is about high school girl who had her walk-man with her all the time. I believe she had pink hair and her name might be lisa later in a movie. I am not sure how did she make a transition to another world but I remember she somehow managed to reach a kind of a ancient, kind of abandoned world. After falling in a type of flower she transformed herself into a warrior with purple close (I think). She found an ancient machine that she could somehow control. The machine was kind of a red airplane and she was flying around. There was a speaking, wise dog involved. Vaguely I remember dog flying with help of its ears. Of course enemy ship arrives, the fight starts. She was captured on enemy ship and lost her consciousness. The enemy wanted to reach planet earth and opened the portal in the sky by controlling her while she is asleep. Her walk-man plays important role because as if she remembers a music, her walks, a boy she liked she woke up, start fighting and stopped enemies coming to our planet. Also vaguely I remember enemy being in a shape of a talking heart (of the ship) which bled and exploded at the end.
I also believe that there was a huge can looking robot on her side, fighting along with her. At the end, naturally she returns to the earth and talks to the boy she likes, for the first time.

It would be great if anybody could help me with identifying this movie. I saw it looong time ago, and it is one of those films that represents your childhood in a way. It is kind of annoying not being able to find any good hints online by googling it.