I have the knowledge on how to change a flat and also the tube. What I lack is faith in my skills. I have changed flats and then brought them to a bike store to have them double check. I do not carry tools to fix anything at this time as I lost my rack bag on a road while my bike was on the back of my car while I was driving home from a short 2 day tour last summer. I have yet to replace the bag(can't find the same one). And I do not have mechanical aptitude which I think is very necessary in fixing all things bike related.
Though on the other end of this I did once get a flat 1 mile from work while the temp was a chilly 21 f degrees at 5:30 am. I would not even think about changing it at that temp in the darkness on the side of the road. I walked the bike to work. I try and not bother other
people with situations I put myself in.