Hi Torquoise,
I don't know if I'll be of any help, just want to let you know that I feel for you, as I struggle with self-doubt too. To tell you just one eample... I graduated Masters last week with the best grade possible. After my oral exam and everything, instead of being all happy, I started thinking of an expression at the oral exam that I didn't say correctly, and about all the eeeem's in between when I coudn't remember the right thing to say.
My friends were there at the exam as it was open for public, and they say that my reaction was downright funny. It didn't seem funny to me, but I'm trying every single day to keep these self-doubting thoughts away. I think a huge part of this is due to perfectionism. Do you feel you have to be perfect at everything?