I myself just did the same damage about 1 1/2 weeks ago. Been taking anti-inflammatory meds everyday and still only slightly better. I have since purchased the Bengio rib protector which was recommended by many here as well as get low profile seat bolts and add seat padding.
My race is in 1 1/2 weeks and being my first season I am dying to race. Everything I have read is that it can take anywhere from 3-10 weeks of rest and that if not rested properly you will do more damage and be fighting the injury for a longtime. With that said, I am hoping I make the right decision to race or not come the following weekend.