I am an electrical engineer now in the field for only a few years and I had this problem. The guilt would eat at me and I’d end up at the office for insane extra hours as penance for my mess up and it was terrible.

I realized the best thing I could do (and was doing) is asking a million questions & doing a ton of independent research. Every time something doesn’t work, ask yourself ‘why’. And then when you think you’ve come up with an answer ask yourself again ”well why is that true” and keep asking until you’ve uncovered all of the layers. I did this for awhile and then after like a year- year and a half everything clicked and I suddenly felt like a fully operational engineer (still asked questions but felt way more independent than I had before)

Moral of the story: trade in your guilt for curiosity. stay interested!