not sad. Honestly, I've worked at Dunkin donuts as a seasonal job and it's hard. HARD. And you're stuck doing all the dirty work that people take totally for granted then having to deal with customers freaking out because they got their order a SECOND late or something. Grrrrr. It can really REALLY bad for self esteem.
So i get where you're coming from. I think a job is a good thing to have IF you can manage it. Makes you feel independent and starts getting some money for you to spend or save *or both*. But right now school and your health should be most important. What are your goals past school? Are you thinking of college? What kind of job would you like instead of Hortons or something similar?
Tough questions, but these questions also come with the age
PS - I'm just about to graduate college and I wish I'd TRULY asked myself these career questions sooner than I did.