Attending the hospital with my mother, an OPD nurse, had been a usual occurrence
"Attending the hospital"? It does not deliver any proper meaning? I think this line needs to be rephrased. Or you can start with the next line.
maybe you should also include that your interested to hear the story of one of the patient, and it wants you to help them more. something like that... :)
I agree with marizon. It is more convincing if you pick up one particular incident and elaborate on that. While telling that story, you should show your how your interest in this profession grew.