has it caused you to become more insecure abd to constantly doubt yourself??

all those times where i would feel like I could accomplish anything.. times when i had great ideas and felt i could complete them.. yet would fail miserably  when i would attempt them.. realize i don't actually know what i am doing or realize i am not actually as good as i thought i was..

it has lead me to always doubt myself even when i am manic. I don't have confidence in myself to complete or achieve anything