Pulled muscle doesn't sound nice. As already said, naproxen is a good anti-inflammatory if you do need it. Gentle massage is also helpful if you can get someone to do it for you with nice, warm hands. There's a tricky balance to be had between resting the tissue and keeping it mobile.

And be careful when you get back to work! Back muscle is not strong (it's not bulky like a bicep) so be sure to use your posture (skeleton/bones and the bulky load-bearing muscles - quads and biceps) to take more of the strain.

Hope it all eases up soon.