I really enjoy reading this post @jaynie, it's normal to think it may be a trick of mind, that's what people always say to persons with these kind of experiences in their life. But, persons with these kind of experiences KNOW that is nor a trick of your mind.
If you have had previous experiences before, and you said there were different in a bad way, and then you think you saw an archangel, I think you are doing it great. Angels has like an army structure, there are guardians angels ( the closest to human kind) and in a superior level are the Archangels, they are more powerful.
If you think it was an archangel, I think you believe in God, so, pray for protection. Angels are there to help us, but we have to ask their help.
Ask them , always. Have a blessed day.
Thank you for your insightful input :)