Argh, now you're truly terrifying me.
Don't be too scared, I'm sure it's different for everyone. I haven't ever had any issues and I've been off it for years. My period is really regular and has been since going off it. I use the Fertility Awareness Method to track it and I know the day before/the morning of the day it starts that it's going to start, so it's not unpredictable for me (I really did like knowing exactly when it would start when I was on the pill).
I saw the comment about hair loss and now I wonder if stopping the pill had anything to do with my hair thinning. Also, I feel better off the pill, but I stopped about 8-9 years ago, so it's hard to remember what I felt at the time. I had been on it for about 5-6 years.