I did mine a few months ago – Summersault with a flourish – landed with the handlebars in me ribs. I wouldn’t bother going to hospital unless you have any other symptoms (dodgy breathing etc.) It’s a long and boring wait and there’s nothing they can do for it. They won’t X-Ray it anyway so you won’t be any the wiser really.
In my case, A&E examined me and told me “it’s broken, stay off your bike for six weeks) I went to my GP the next day and she said: “it’s bruised, you can ride your bike as long as it doesn’t hurt too much”. Clearly, she knows what she’s talking about 😉
If you need to cough or sneeze (as said above, DON’T suppress a cough reflex, it’s an important lung clearing mechanism that prevents infection) brace yourself with your arm and it won’t hurt so much. I found riding wasn’t too bad…. Turning over in bed was the worst.