I would say you are none of the above. You are like you said an accountant technician which is different. When asking for an accountant they normally mean a chartered accountant like a CIMA or CIPFA qualified.
When I did AAT it was the equivalent of NVQ Level 4. This may have changed. Like you I am not clear on the difference and to be honest I have never thought about it.
AAT is a good base to go on to a chartered accountants qualification and obviously would mean more options and career development.
As a rule of thumb, a technician can prepare the accounts and basically do all the leg work but only a chartered accountant can actually sign the accounts off.
The difference between an internal and external accountant is that with internal it means you work within the company and on their payroll. An external accountant would be working for a group of accountants who are employed to go into a business to effectively do their accounts. An accountant in this case could be someone who is self-employed.
Hope this helps you some of the way.