Pinked my CMEL many years ago for what I considered at the time to be pretty ridiculous... and still do today quite honestly...
Instead of presenting it as that - I thoughtfully crafted it as a mistake that I learned from - that’s all they want to hear - own it - learn from it and how it made you better today (ever since then I’ve created a habit of this or that... I used it as a teaching point with my students, etc..) it’s honestly not a big deal.. it’s all about taking that turd and shining it into a beautiful diamond.
I remember feeling the same way you did after that... thought my career was toast.. that type of feeling is natural in pilots, most of us are pretty type A perfectionists - it’s ok to fail (so long as it’s not reckless and/or fatal)...SOPs, FOMs, regs, AOMs and on and on are written and developed through failure. We learn from it and become better..
It worked out for me.. eventually became a LCA at my old regional and untimely got picked up by Brown. Hang in there!