That's very possible. Depending on how you grew up, your religious background, the political climate while you were growing up you may have ignored any and all affections you may have had towards other women.
For some women, once they have a late life romance with a woman they are able to trace back in their memories and identify incidences they had with women. They realize they had crushes on their friends or female teachers. They may realize they connected in a different with fictional female characters in books, movies and artists.
Some women may even notice that something was always missing. They never connected with what the other straight women were saying and experiencing with men. Even in their own relationships they've never experienced the level of joy and connection they heard other women speaking about. They could not pinpoint it but always knew something was different with their own experiences.
For other women, the feelings are new because our sexuality is a fluid phenomenon. This is their first crush or romantic relationship.
Both of these situations are valid. Your sexual identity is a personal experience and absolutely unique to you.
It is certainly possible that you have been attracted to women your whole life and because of societal pressures you were able to successfully suppress it until now. It is also entirely possible this is a new experience and attraction.
Which one of these situations resonate with you? Put it in the comments.