I just tell people when it can be done without me shuffling my priorities around (or whatever shuffling makes sense in my head and doesn’t stress me out). Perhaps I’m lucky, but 95% of the time the person asking doesn’t care. People are really keen to “get things taken care of” but “I spoke to this person and then said they could get it by next Tuesday” often ticks that box just fine.
In that last 5% when someone doesn’t like the timeline I’ve provided for them, I just let them know what’s ahead of them in my work queue. 95% of the time after that they realize that they are talking to the wrong person if they want to cut in line. That last 5% of the 5% when someone really wants to press the issue, I just suggest we get a manager to help decide what the priorities should be.
Your mileage may vary though, I’ve been pretty fortunate to work at places that expect a lot but also don’t expect the impossible. I’ve definitely gotten the “can’t we find some way to get it done by X” I have taken to just responding “not unless you’d like me to work outside of our working hours.” It sorta flips the tables, I’m not saying “no” but I’m making very explicit the shitty thing they want me to do and I’m requiring them to take the affirmative action of saying “yes, I want you to work outside of working hours.”
I wouldn’t stay somewhere where that happened frequently, but being able to say that is a luxury many people don’t have. In any case, maybe you will find some success with these strategies, I’ve found them to be pretty effective and they seemed to be received much better than just saying “no” and it has the nice side effect of you looking reasonable and organized.
I was an absolute door mat style of people pleaser. I just started saying no to people about things that were low-risk, and seeing what happened. I still get massive anxiety from it, but I can say no like a champion now. Probably a little too often, if I'm honest.
I did not seek out therapy, but probably should've.
If you're looking for advice - spend some time on this. My experience is that people who have negative personality traits, and try to blame the way they were raised, are not taken serious as adults in the working world.
If you're not looking for advice - then just tell me to fuck right off back to where I came from. No problem, either way.
(saying no doesnt mean you say it out loud. there are a thousand ways to say no)