Is not the very fact that you had been sent home is reassuring? - if serious, he must have admitted you then and there! You might even have had it from birth and detected just now!
Incomplete Right Bundle Branch Block
(RBBB) by itself is not a cause for serious concern.
The heart like all other organs in the body, has blood vessels and nerves. The nerve branches to right and left bundle. A delay in conduction is called block.
RBBB is sometimes normally seen in some people! It can also be due to heart problem - right heart problems - volume overload like Atrial Septal Defect
/ disease of conduction system itself and so on.
Your cardiologist may do more investigations to assess and assure
All the best