The use case to model is the register of a new appointment.

The user logins in the system as a patient (role). To make an appointment shoudl enter medical specialty and date. System shoudl look for the doctors availables for that specialty on that date. From the results patient should choose one and then system save the appointment. At the end user shoudl receive an email with the information of the appointment.

The classes that I have in my model are: User PAtient Doctor Appointment DoctorShcedule and some more but I think these ones will be involve.

I have this initial sequnce diagram:

I have problem to set the return messages and also with the email step.

Thanks