CWOs do keep appointments in general, but there can always be an exception - she may have been delayed at another visit, may not have been in work today (with no replacement officer, or a replacement officer who wasn't aware of your appt), or, heaven forbid, she may have had an incident in her clinic or at another visit so was unable to get to you or to contact you.
Give her a call on Monday and re-arrange the appointment.
By the way, if you had mentioned your dental appointment to the CWO when the visit was being arranged, she may have been able to adjust her schedule to suit you? Worth remembering in case it clashes again.