Unwanted Concern

I made the mistake of bringing together a couple of my friends and the situation has led to some unwanted concern about me.  During the last week of so, a couple of my female friends brought up the topic of going walking to get in shape.  I came up with the brilliant idea of all of us walking together - strength in numbers kind of mentality.  The three of us went walking yesterday and things went fine.  I was unable to join them today because I had to drive out of town.  They met up to walk and the topic of conversation was me.  All I can say is after today's walk, one of my friends has a whole new understanding of my personal life and is more concerned about my well being than I would like her to be.  I appreciate the gesture but I do not want anyone losing sleep or stressing over what I deal with on a daily basis at home.