Appropriate designation - handling payroll & accounting and HR activities

I work in small company with around 50 employees. I handle payroll & accounting.
In the absence of HR, i also perform HR activities. As of now my designation is accounts specialist.
I need an appropriate designation which includes all the above mentioned activities of accounting and HR.

This is mostly depending on your reporting Officer / Manager, Since you are handling payroll & accounting, if you are reporting to an Officer, then your designation could be Junior Officer. If the reporting authority is Manager / Plant Manger, then your designation could be Executive

What is your actual designation ? No comoany will give a designation as account specialist unless you are handling customer accounts in a bpo