There is some mythical unicorn out there that other people claim exist. This unicorn is a job that you love so much, that you'd do it willingly and for free, but you still get paid handsomely for it. For you, stocking shelves likely is not that unicorn.
However, let me tell you from my experience what having a job like that is like. When I was poor and on the verge of homelessness, I worked for a temp agency. I worked at factories, warehouses, paper mills, construction, etc. Basically low-grade immigrant work. I'm going to fast forward a bit and tell you what other jobs I had since then: instructor, driver, tutor, lab technician + manager, research assistant, editor, consultant, others I'm probably forgetting.
Let me tell you, I got paid peanuts ($6.25/hour before tax) working through that first temp agency. But it was the fucking happiest job of my life. I would run around like crazy, making boxes, palletizing, opening product, running compost and recycling, cleaning with chemicals, whatever. I did it all. 11 hour shifts. After I learned the ropes, fell into a comfortable rhythm, and figured out the most efficient way to do every minor task, I would come into work and just autopilot. Smooth sailing for hours. It was like getting paid to go to the gym. I got in the best shape of my life. I began getting called in for overtime, getting paid $11/hour then, working 6 days a week. Manage to afford to rent a house on my own with a pool. Bought all the booze, weed, and drugs I wanted. Full independence, paid to stay in shape and lift things, plentiful drugs and alcohol, all at age 18. What more could you want?
My life unfortunately didn't continue further down that path, but let me tell you, even though I make 5-10x more money now than I did back then, I hate my job(s) so much more than I hated that simple factory job. It's so liberating to just be active all day and not have to think about shit, solve other people's problems, manage people, negotiate, etc. Fuck. I wish I could go back, but now it would be stupid to do so given my current income.
TL;DR: Try to make the most of it. It will get better if you don't resist. Then it will be smooth sailing, and money in your wallet. Money in your wallet grants you independence. Independence grants you freedom. Focus on the end goal and you'll get through the rough patches.