Those people are bastards. Nothing to worry about. Be yourself.
You don't have anything to worry about. You can take things at your own pace and we all day dream from time to time. It seems your past employers just aren't very nice. You will do well in any given opportunity as long is you do what is required to your best ability :)
then change it, be more alert and "in the moment"
Don't listen to others judgments, just do you.