What you can expect is a journey into the unknown. You could experience flashes of different time periods. It might be like watching a movie in your mind, with scenes of a different era playing out. You may see yourself in different clothing, doing different jobs. And it could also be a very spiritual experience. It might make you feel more connected to the universe, as if you're part of a bigger cycle of life and death and rebirth.
Well, you can expect a lot of things. You might have vivid memories of places you've never been to in this life. For example, you could recall the layout of an old city or the smell of a particular type of flower that doesn't grow near you now. It could also bring up strong emotions related to past relationships, like a deep sense of love or loss for someone you don't know in this life. Sometimes, it might even make you aware of skills or talents that seem to come from nowhere in this life but were perhaps developed in a past life.
You may expect to gain a deeper understanding of your current self. The memories from a past life regression could help you figure out why you have certain fears or phobias. For instance, if you have a fear of water and in your past life regression, you recall drowning, it could be the root of your current fear. Also, you might find that some of your personality traits make more sense. Maybe you're very drawn to a certain culture, and through past life regression, you discover that you had a past life in that culture.