Blind Spots in the road never taken
Often, when we do things we overlook things and don't see the blind spots. In retrospect they look stupid and trivial to point that you get harsh on yourself. You often say things to yourself like "how can you be so dumb?" and "i should have been careful and not so naive". You start questioning your ability and it takes a great hit on your self-esteem.
As it is said "hindsight is the best insight". Looking back at things it is easier to say i should have done things differently. Just the realisation that you would do it differently is something to be celebrated and sign of growth. It is simply "Being Human" that you're naive at times and you have many blind spots in your thinking. It is perfectly normal and it should be embraced that you would have less blind spots in the future and it should be treated as experience. Experience is something that cannot be taught.
Just be kind to yourself. Embrace the challenges as an opportunity to know your limits and discover yourself better. What you regret the most is the road never taken and it is perfectly human and normal that you'll have blind spots when you explore new challenges.