You may find yourself sitting down at your creative work and doing something easy; parallel to this, you may notice your mind reaching for something else, something difficult.
I, at least, have a tendency when creating things to do what's hard for me, not easy. I think this is coloured by a shallow comparison with the works of others. For instance, if I write music, I may feel a suggestion towards an obvious next bar; but at that moment, a perverse inclination intrudes and discards it, looking for something more... well, more what?
The something more isn't there. The obvious idea remains a moment, fades, and I gradually lose the inclination to compose. I feel stuck.
Well, I'm not stuck. I've simply convinced myself that what comes naturally to me is not right.
It was helpful for me to realize that what's easy for me is hard for others. And vice versa!
Obviously, lots of people will be above your level creatively. But recognize that what you do trivially-- that is also your voice.
There's a genuine time for criticality of your own work. It's when you don't like it. Chuck it when it feels bad and put something else in.
You can be cavalier with discarding ideas when you don't censor and block yourself up-front. If you just get your work out uncritically without wringing yourself dry in a futile search for a nonexistant more, well then— it's not a big deal to turf the bad work, either.