This is totally awesome, @sahillavingia. For a young guy, you have learned some incredible lessons about business in a VERY short time. You are positioned well to build that billion dollar venture that you originally dreamed of. It might not be called Gumroad, but who cares?
"It doesn’t matter how amazing your product is, or how fast you ship features. The market you’re in will determine most of your growth."
This is so utterly, absolutely, painfully true. We hear stories of hypergrowth as if you can just choose that path and it magically happens. Reality is: most companies never get to hypergrowth. Your only real option is to pick a large potential market with a reasonable hypothesis for getting there. And then see what happens.