I have similar feelings, I started my own startup just out of college and feel like that was a waste of time. I had never shipped any code more than college as

I have similar feelings, I started my own startup just out of college and feel like that was a waste of time. I had never shipped any code more than college assignments, there were some classes on entrepreneurship and business but they were so shallow, I had no professional experience and little knowledge outside of academia, I had no network or audience, I didn't know how to run a team which consisted of my college buddies. After working in a big corporation, big startup, bootstrapped startup and more environments I feel way more prepared and motivated, I know now how to do most of the things I didn't, I have a much bigger network and I know how an actual workplace functions and I feel confident enough I can do it myself.