Day 32 My big mistake enraged me : analyze, what to do, feasibility

Context
I was working on a big recap email to my most important person in healthcare sector that can help me about my project to work for french TMSer . I worked so hard at it, and with so much pressure, that I stopped late to go for an appointment, and forgot to click on "Send" button. And I discovered that 1 month afterwards !!!

Rage
I was so enraged about my self, told me I'm an idiot, that I missed all opportunities, that I could never make it anymore before my second child will be born... That I again put too much pressure with myself, and miss an inexcusable final part. That what he will think about me : he is not serious, I cannot trust him, he is not good enough, he does not seriously work at this project. I rushed to read it again, add a "sorry part" at the top and send it with keep complaining about this to myself and to my wife and friends.

Analyse
I realise writing that, that I was very hard with me, and let enter and grow a lot of negative automatic thoughts, that I amplified with ruminating and speaking with others.

Ideas
Maybe I should have stopped, breathe, let emotion arised and felt it, think why, and what appropriate response I want to make about it on me inside and with the outside.
- inside : take care of my inner child, you have the right to some failures, you're still great and loveable; plus let thougths passed and do not "enter the train" by continuing to think and do what I was doing juste before.
- outside : I can share my feeling once at a few persons

Really possible?
Not very convince I am capable of doing this entirely (to not say "perfectly" ha ha ), but happy to know how to analyze it. And I hope by this SEP program and keep writing it, it will stick deep in my gut level ! And maybe I already applied it a little unconsciously...