On the other hand, my work is not that stressful, and I'm still going to school so my job is very flexible on time.
Anyone else been in a position like me?
You can relax, but you might not want to. My salary has been artificially lowered because every previous company likes to make an offer based on your previous salary, or I've made so little that I had no savings and had to take the first job offered to me every time. It wears on you after awhile, and I probably could have made a lot, lot more money if I made better choices earlier (although I also wouldn't have some of the wide range of job and life experiences also, so there's that).
But every once in awhile it's nice to take a breather, sit back, recalibrate yourself, get your work/life balance back in check, work on some creative things in your spare time, etc. Easier, non-stressful jobs will allow that. So I guess it's wherever you need to be in life right now and how much you need to be compensated.
But if you're not getting challenged at your work, you're probably not learning skills that are in demand and your next job hunt will probably be more difficult.
I made $25/hr (without benefits), then got dropped to ~ $18ish / hr (with 401k matching and health insurance) at the part time job I worked while I was in school.
I worked 20 hrs a week, completely remotely, and was responsible for some of the NMS systems and Linux admin work at a large satellite operator. It was a mix of sysadmin and software engineering, and I learned a ton.
There were a few stressful moments, as I was on call, but my boss tried to shield me from it as much as he could because he wanted me to be able to focus on school.
If you're a full time undergrad student, then my advice to you is to enjoy what you have right now, as long as it allows you to focus on your friends and education. Having practical, hands-on experience from work will greatly complement your coursework, and if you can get that experience without being in a high-pressure role, then it's a win-win situation for you.
Consider asking for a pay bump if you think you're undervalued, but do research on what other paid SWE internships are at, and consider the fact that a bump in pay may cause your boss to have higher expectations of your output.
By competitive, I mean microsoft, facebook, and google. This could be naïve of me, but that's how they position themselves.