Hazelgirl, I am sorry you had such a crap day.. And I can say all the things that others have said already - It will pass, be kind to yourself, don't take what your co-workers said to heart too much..

But I also -in addition- want to say this. Sometimes the saying is true that we have in Germany (don't know if you have it where you are)
"What you shout into the forest echoes back at you".
When we feel down or upset, depressed or angry or stressed - that's what we usually signal to our surroundings. And sometimes we don't realize when we're negative or sarcastic or blunt or whatever.
Others pick up our signals and overlook the cause of why we do things or say things or behave a certain way. So we hit a certain spot in others because they too have their reasons for reacting the way they do. And then we take their reaction very personally and it hurts our egos and confidence.

But, instead of just feeling like you are pushing people away (and we all think or feel like at at some point and it makes us even more negative about ourselves or the world) it sometimes helps to turn it around with the exact opposite. You know, try to be the bigger person - in yourself and to others. That friend who asked if you can never say anything nice - tell them something really nice instead of apologizing for making a joke you thought was ok to make. The co-worker who teased you all day, in your mind forgive her and think something nice about her. (Or in your mind, think all the bad things about her you can imagine and allow yourself to be very arrogant and think you are much better than her :-) That helps me sometimes and it eventually balances out to neutrality)

Take your comment that you think was inconsiderate and turn it around into something positive - for example - think to yourself it was absolutely ok to say it because that is how you felt and it just came out like that. Try to be a little gentler to yourself, refuse to believe what the situation tells you about yourself because I am convinced the feelings you feel about yourself are lies that others put on you today and in the past, but you take them on because that's how it made you feel.

I hope you find some rest this weekend and the the exhaustion fades a little. You are quite awesome, I read your posts and think you have a lot of strength! Draw from that when you feel so low and bathe a little in the love people have on here for you!

Love,
Amelia