Confronting to Mistakes

I missed one delivery at work today. I understood some requirements differently. I even tested the tool thoroughly before delivery but somehow skipped few things. The issue was escalated to my boss and I had to face the consequences. 'Shreya?.. yes she is working on that', that's all I could hear as the boss kept the phone down. I knew I was in for some explanation. The boss was super helpful - did not outburst at me at all. But did ask for details on what went wrong and then based on what I had to say, asked me to cancel my meetings with clients so that I have more time to fix issues before we go ahead.
All this happened just a while ago. I want to pen down my thoughts now itself otherwise these emotions would just pass by and I would not want to remember them again to write them down.
How did I feel while all this was going on? I was feeling bad, very bad. I felt like I made a mistake, because I thought it was my responsibility to be correct. Being wrong was not correct at anytime, right?
As I was talking to my boss, I consciously tried to be logical. I was trying to be correct even in telling the reason why I made a mistake. No, I was not defending my self. May be it was a moment where I knew that something was wrong and at the same time was feeling bad about it. And believe it or not, I was also trying to be consciously aware of my emotions.
I starting telling myself, don't take it personally. All this is related to the work you did or did not do. And it is NOT related to YOU. Be professional. Work does not define who you are. As I walked out of office, I apologised to my boss. He said, things happen!
I know things happen! And I was also trying hard to tell my self this. But I was not able to control my emotions. I felt bad about something. Why did I have to feel bad? What was it that was troubling me?
I was not even thinking about the consequences of the problem on hand. I was not worried that professionally it marked bad on me. It was not such a big deal. But I was and I am feeling sad. Is this ego? Am I thinking of myself as a perfectionist that can never go wrong? I believe it is bit of both.
I just know that mistakes are part of life. But I just don't know how to handle the emotions that run alongside. Knowing and making this knowledge a part of you is how you grow in life.
I am glad that I was part of this experience. It just makes me understand how much vulnerable I still am to life's challenges and how much more I need to learn and grow in life. I wonder how I still have not been ready to grow yet!