Remember, You Are A Human. Not A Doormat!
The Doormat Is Never Given Special Attention.
People know the dirt in their shoes. And the amount of dirt they have been carrying all this time.
Saying "NO" will not make you a bad person. It only highlights your privilege, self esteem and adds dignity to your existence.
The more you say "YES", the more people will take advantage of you. They will take you and your favor for granted. It's not your fault — people all around the world are just like that by default!
Just like how man misuses nature and her offerings and services; takes her for granted despite the fact that she gives them all for free; he would misuse your favors too!
You need not say NO for everything as well. Learn to prioritize. First yourself then the others.
When you say No, if they get offended as say "What personal business? You did it all these days..Can't you….bla bla" then understand that they were just using you all this time and you've been their Doormat!
If they understand and if they have been grateful, they will smile without any hesitation and say "alright! No probs!". They will understand and respect your personal space.
Next time when someone asks to get their "Regular Coffee" on your way to office, tell them "NO, I can't because I need to take care of some personal business".
When someone asks you for your password, tell them "NO, It is called password for a reason. I can't share it with you".
Remember, You Are A Human.