I am uncomfortable with myself today :(

I want to ask of someone has experienced something similar to what I feel..

With certain situations I get a very upsetting anxious an uncomfortable feeling, for example, I work in mkt, but unfortunately sometimes i have to do things that are out of my expertise, some months ago I had to investigate some information from our competitors, and I didnt find all the information I needed online, so my boss told me to call them as if I was a customer, I know this is not rare in my field but I had never done it, so I gave my real name, my real number and email and acted as a customer. Fast forward to this week, my company is making an alliance with this competitors and I was added to a whatsapp group where the person I talked to that time is also added. When I saw her number I even got a tingling sensation on my legs, I felt super anxious and uncomfortable, my bf told me to tell my boss so there's not a misunderstanding or something weird in the future, i did and she told me it was not a problem, but still I feel super uncomfortable, like I made a mistake and I feel dumb.

My boss told me there's no problem, this girl is probably not aware yet, and i know its not a big deal, but it FEELS like a big deal, I have been coming back to think about it all day and it is affecting me.

My question is, if I rationally have the information to know this is not important, why do I feel like it is? Why do I feel vulnerable, or dumb, or anxious? I dont understand it and this is something I have experienced many times in my life, always making me feel uneasy :(