Ruby, is this at the same job where you were recently sent home after sending a customer to a kiosk and then arguing with the manager and then going over their head? I ask because lots of problematic behavior can lead to being fired. I know if I yelled at my supervisor...well, I'm sure there would be disciplinary action.

Regardless of the reason, yelling in the workplace is not acceptable. It doesn't matter if you were upset. It doesn't matter if he was being standoffish to you because he was in a bad mood. It sounds like your supervisor was in a bad mood, and you equated that to being mad at you, even though he said he's not. You're trying to read people's minds and that never works out. If someone says they aren't mad at you, then all you can do is take them at face value and believe them. If they appear to be in a bad mood, then let them be in a bad mood. It's not your mood to manage, it's theirs. It seems you often worry too much about what others are thinking and doing and not focusing on what you are thinking and doing. I think it would be really good for you, the next time you are worried if someone is mad at you or anything similar to say to yourself "what is my job today?" and focus yourself on that. You're kind of embroiling yourself in drama and creating problems that don't need to be created by worrying about things that aren't yours to worry about. It really doesn't matter if he's mad at you or anyone else. That is for him to deal with. It was okay to ask, since you sensed he was in a bad mood, and obviously if he was mad at you, you'd want to find out why and if you need to do anything to address it. But after that, you have to drop it and let it go.

I work with many people, and we do try to be open if we're experiencing something but if someone communicates something to me, I don't read into it. If I get a short response, I don't read into that person being mad at me. Most of the time they're just going through email quickly and don't have much time to reply other than yes/no, thx. No small talk. I used to read into it that ppl were being short with me. Now I just go by the mantra that if someone has something they need to address with me then they will. I won't carry their moods or problems in my head for them. And I won't worry about it before it happens, because there's nothing I can do. Not all work places as so honest and open as ours, but still, you asked, he answered, the thing to do would have been let him have his bad mood, and believe him that it didn't have anything to do with you. What it sounds like happened is that you didn't believe him, and therefore retaliated with a poor attitude. You can't let other people's moods affect yours.

So, to answer the thread question: the best way to know if someone is mad at you is to ask. If they say no, then leave it alone. It's not your job to read their mind. If they are lying and are mad at you, then they are manipulating and it's not your job to deal with their emotions. If they say yes, then ask how you can resolve it. If they say no and appear to be upset, and it's appropriate, ask if there's anything you can do because they seem not as their usual self, as another poster mentioned.

But in general, at work, just focus on yourself and your job.