I never found out whether mine was broken or sprained as they wouldn’t X-ray it. (it makes little difference anyway as treatment is the same – nothing!)
A&E doctor said: “it’s broken, don’t ride your bike for 6 weeks”. GP said: “It’s sprained, you can ride your bike as long as it doesn’t hurt too much”. So I decided that A&E guy doesn’t know what he’s talking about 😉
It was much better after 2 weeks and completely better after 6. Actually after 2 weeks it was pretty much fine except for lying down and sneezing (you sneeze a lot more with a broken rib, **** knows why!) No symptoms since.
2 tips: as above, they told me in A&E you mustn’t just take shallow breaths as you can get an infection. and if you think you’re going to sneeze, tuck your arms in to brace your rib cage and mutter: “oh crap!…”