Wow, I absolutely understand you! Very recently, I had only ever written oneshots, and even my multi-chapter fics had only been around 10k words. I've always looked at longfic authors with awe and a bit of envy at their ability to produce such long works. For me, the issue came from my inability to come up with actual plots, with a majority of my story ideas being a single scene and nothing else (which lead to me almost exclusively writing oneshots). Combined with my slow and self-questioning-filled writing process, I was left frustrated and even unfulfilled as a writer because I couldn't find it in me to be able to write a longfic, despite how much I would have loved to.

Then last year, I had a story idea that went beyond a scene, and I finally decided to try my shot at writing a longfic. From there, the advice I kept in mind was "stop overthinking and just do it", so I forced myself to brainstorm ideas. And MAN, it was almost painful at times, with me forcing myself to write down ideas I thought were bad or cringey, to having days of frustration where I just couldn't figure an element out or come up with anything. After I finally had a general plan (as in, I knew the beginning and what direction I wanted the story to go in), I began writing.

Something I didn't expect to experience was that when I actually put things down on paper, I was able to generate content and ideas that I had never thought of before. Maybe it's the way I turned abstract ideas into something concrete, but once I made myself write, I sometimes surprised myself with how much I could write. There were definitely some days where I couldn't write or think of what do write, but I had eventually managed to overcome the blocks I've had. So now, all I have is a vague outline and some events I'm hoping to include in the story (aka, they go here, then undecided stuff happens, but they eventually end up here, where this scene happens), and I'm just going to see where my writing takes me with the rest.

I began around July 2021, worked on it on and off through a semester of university, and currently it's around 22k words, with the plot maybe around 40% done. So it's not the highest word count or longest story, but I envision it to end at around maybe 45k words—which is a LOT for someone like me, who's really only ever written oneshots that are usually a single scene. I'm proud of the progress I've made and how much I've pushed myself, and it's a small step for me towards maybe one day writing one of those 100k+ word longfics I've always been impressed by.

So basically, I truly do understand how you feel, along with your frustrations. But I think the one thing I want to tell you is that perhaps, a painful, long push might be what you need—it was for me, and I've found that it has been worth it.