Is It Wrong to Leave an Unpaid Internship After Completing the Full Duration?

I’m a Computer Science Engineering student and recently completed a 3-month unpaid internship at a startup. This was my first-ever internship, and the experience was honestly a mixed bag.

There was no formal tech team in the company. The entire system was being built by interns like me, with no technical mentorship or guidance. Despite that, I gave my full effort and completed the work that was assigned using a specific tech stack.

Midway through, the project’s entire tech stack was suddenly changed without proper team discussion. This resulted in most of our previous work being discarded, and I was asked to rebuild everything solo using the new stack, while others moved to different tasks.

Meanwhile, college reopened, and I now have a 3+ hour daily commute plus other mandatory academic responsibilities. I informed the faculty and intern team that I would not be able to continue. However, I faced pressure to extend my internship, with comments like "leaving now could harm relations" and “you should finish the project, not just the time.”

That said, I’ve completed my entire 3-month duration, which was the original agreement. I have not abandoned the work mid-way and have exited respectfully. I’ve also been told that a replacement intern will be arranged, though I’m not responsible for that part.

I’m now planning to request a certificate of duration directly from the company to reflect my contribution.

Was this internship setup exploitative, or just poor management?

Am I wrong for walking away after fulfilling the agreed time commitment, even if the project isn’t complete?

Has anyone else faced something like this?