Work Complications due to pain

For the last year or so I've been dealing with sciatica flare ups off and on. In October 2024 I got this great line cook job that I really really love. Since the end of November however, my sciatica has returned with a vengeance. I am in such intense pain day to day and I have no idea how to deal with it. I work 30+ hours a week and I'm on my feet for that entire time. If I'm not standing, I'm bending over, lifting boxes, or moving in some kind of way. In the last few months I've been taking otc painkillers every single work day just to manage with the pain (I regularly take about 2500mgs of ibuprofen a day). I rely heavily on this job and care about the work im doing. I've been doing stretches morning and night to try and minimize the pain but I fear with my work it seems to have only gotten worse. I go to work with a back brace, take painkillers, stretch, walk regularly, and am working on losing weight. I'm 21 years old and I can't get up in the morning without being in agony. If anyone has any different advice I would love to hear it because honestly im miserable each time I go to work, go to bed, sit down, get up, LITTERALLY ANY TIME I MOVE. I feel like i'm too young to be in so much pain and I feel like it's my fault in some way. Any advice is appreciated but especially if its different than what i've already listed above. (I have this great doctor too but i'm not sure how to advocate for myself 😅.)