Well, the meds I got on Sunday seem to be doing the trick. I took most of Monday off work and all of Tuesday but managed to work full shifts the past two days. My back is still twingy and sore but the crippling agony that I was experiencing over the weekend is essentially gone. I should be back to normal by the weekend (just in time for more work!) which is about when my pills run out.
I need to get to work doing crunches and other muscle strengthening exercises to get my core muscles in shape so I don't do anything crazy to my back again!