I’ve only had one regression, done by a professional about 23 years ago. I, like you, wondered if I was just making it up. I felt like I was just talking as I went along or seeing stuff that really wasn’t accurate. As the regression progressed I felt more ‘under’ and I didn’t doubt myself as much. I never had another regression and wondered for years if I had done mine ‘wrong’ and didn’t talk too much about it. Years later I was talking about regression among some friends and it seems like that feeling of having made stuff up is common. Their recommendation, though I didn’t do this myself, is to keep up with the regressions because they come easier with time. Just like with anything, the more practice and experience you have, the better results!