ANSWER:

What you are doing is extreme and would turn you into an ocd patient!

Nobody works 100% of the time on duty! As long as you are fulfilling your tasks as per the job requirement and your supervisor is happy with your performance, you are fine. 

 

I work 7.4 hours a day in a factory. I regularly drive myself crazy in my head as to whether I am working every minute. often this is not the case and then I count the minutes that I have not worked throughout the day (mostly the amount of minutes lost because of too long break, like 1-2minutes per break) Sometimes I work these minutes at the end of the day, is this necessary? or