You have an impressive amount of self awareness - I think that's by far the most valuable thing one can possess. Some suggestions:

a) Push the baby out by this week. If you're anything like me, the improvement in your actual project will be exponential.

b) This is a little harder to explain, but I'll do my best. I've felt inadequate many times in my life, and it can be paralyzing.

You need to be OK with failure, because life is full of it. That doesn't mean you should accept it, but it means that your worth shouldn't be defined through being successful, and you shouldn't be crushed by failure. How you do that is really up to you - I've found my own way - but once you're OK with that, you won't feel like you have to "earn" your breaks, and the need to perfect things will decrease.

I hope this is helpful. I don't want to offer more advice than I can chew, but I wanted to at least say something. Feel free to shoot me a message.