Hi Azure,
I don't know what "hit him on the hot collar" means and I haven't heard that one before.
We often use "call it a day". You can also say "We have decided to call it a day", or you could say "We are calling it a day." For anyone else who wants to know, that means that we are not going to do any more work now until tomorrow.
"On pins and needles" is an interesting one. It means that you are excited and alert as you wait for something. I was on pins and needles waiting to see if he really meant to ask me to marry him that afternoon when he came with the flowers."
"A thorn in my side" isn't just a hurt now, it is a continuing, nagging hurt. "It has always been a thorn" in my side." You know how thorns fester and irritate for quite some time. That's the meaning.
I'm glad to tell you that I had a very nice lunch with a few women I know. We got together to "shoot the breeze." Nobody was "down in the dumps", we were all happy to be together, and eager to talk and find out the news. We all talked together, and nobody was "left out in the cold."
"Shoot the breeze" -- casual talk. Nothing serious at all. It has to do with the windy breath that comes from your mouth when you talk. Maybe "shoot" has something to do with the speed with which it puffs out.
"Down in the dumps". Nobody was depressed.
"Left out in the cold." Everybody was included. You could also say regarding a company that didn't get a contract: "We were left out in the cold." Meaning that we were really cut off.
"Our proposal didn't fly." That means that what we wrote out as a formal proposition about what our company would do for them was not accepted.
"It didn't fly." If you left your office to show a house to prospective buyers that you felt would be very interested, they made an offer to thehomeowners through you, and you presented the offer, but it was not accepted and you could not negotiate a deal you might tell you coworkers who asked how it went that "It didn't fly."
Maryk