Back pain

So I should be starting my new job soon, it's the first time I'll be working since I got pregnant. I'm 22 weeks currently.. I get horrible back pains all the time mostly from being on my feet. What can prevent from my back hurting so badly? I heard a girdle could help? I really hate taking tylenol, I know it's fine during pregnancy but I still do my best to avoid it you know. I just dont want to be in all that pain at work and come home feeling terrible. We really need the money so I need to work for as long as I can til the baby comes. My back just always hurts so badly..

Does anyone use girdles to prevent back pain during pregnancy? I know a lot of you work a ton and on your feet a lot during pregnancy, I just wonder how you do it!