I suggest taking a couple precautions, and I speak from experience. Tell your employer IMMEDIATELY so they will have record of the injury. It may not seem too bad right now, but these things can get worse fast. (My father-in-law injured his back at work and didn't really think anything of it. By that evening he was in the emergency room because he couldn't even stand. 9 years and several surgeries later, he is on long term disability and STILL going through the Workman's Comp law suit. It started off as just a tugging pain, but ended up being MUCH worse.) Once you have done that, try not to lift anything else for the rest of the day. If that is part of your job, then when you tell your employer, request a back brace...OSHA requires them to have one for you or provide one. Make sure that you bend and lift at the knees, not at the waist. When you get home, try heat compresses. God bless and good luck, and PLEASE, not matter how small it may seem, report it to your employer!!!!