Should I be a part time supervisor?

I just completed my 30 day probation last Friday and I’m being offered a part time supervisor position within the company, I’m inclined to take it because of the pay $27 an hour & my health conditions, I have diverticulitis and hemorrhoids, after lifting consistently for 3.5 hours- however long the sort is whenever I get home I start to shit blood and constant diarrhea and there’s a burning tingling sensation throughout the rest of the day in my colon. IF I were to go management I wouldn’t have to lift boxes anymore but I wouldn’t get the pension after 25+ years plus the healthcare insurance for package handlers is better then the healthcare for part time supervisors.

What do you guys think I should do? I’m 20 years old and another thing is I’m starting to develop glaucoma, so if I were to go blind from it, the pension for package handlers would be very good for me if my conditions get worse.

Another reason why I want to stay as a package handler is because of my work/life balance, I’m currently in school for welding and after I graduate I’ll be getting a welding job and stacking it on top of UPS.

I should note I’m also a package handler at FedEx however I don’t get any benefits with them since I switched over to occasional package handler with them due to my hemorrhoids.

My life currently is 3am-8am (FedEx) 9am-2pm (welding school Monday-Thursday ) then I work at UPS 4pm-10pm. Or whenever the sort starts for the day.

With all this into consideration what should I do?