I have pain in my hands and pointer finger knuckles from work, what do I need to do to fix it?

I work in sub assembly and recently I've been assembling the handlebars for atvs, in doing so part of the process is pushing the grips onto the handlebars itself by hand. My hands have been killing me for 2 weeks now and the pain isn't going away, hurts when I squeeze my hands. What do I need to do?