Going back to university after a long break

I’m returning to college in 2026 to do a masters in aerospace, specifically astronautics. I’ve been working in a job as a linux systems engineer for the past five years so I haven’t seen so much as an integral since I graduated from my bachelors in physics. My job uses very little brain power - it’s mainly navigating through hosts, finding the issue, and fixing it. Obviously after a background in physics, it’s not exactly what I dreamed for my future.

At this stage I’m pretty nervous to get back to college. I’m a hard worker, excelled in high school, but was fairly average in my university class (which is common when you put a bunch of high-achievers together to study physics). But I can’t help that nagging feeling in the back of my head saying that it’s not enough. I’m basically starting from scratch at a master level.

I guess my question is has anyone here done this for something similar before? Did you succeed? How did you find it in comparison to students coming straight from undergrad?