Dear Susan,
Glad to see you again here. Before I give my opinions, allow me to sum up your points above.
1. You are interested in English and want to be a translator or interpreter.
2. You have the attempt to quit your present job and to get the job you are interested in.
3. You are not sure about your capability in doing translation.
4. You want some advice.
I am of great honor that I could give my advice to help you out of this dilemma.
My first advice is: Never act before you have a clear picture of the whole thing. Since you are still not sure, I would advice you to stay in your post for the time being. For it can do you some favor now:
1. Your present salary can ensure your economic independence;
2. Your present salary can save some fund for your future study or examinations.
3. Your present job can keep you up with English practice. Although you don’t practice more now, yet you can certainly accumulate some by picking up a little bit day by day.
My second advice is: try to find out what can you do in translation or interpretation. There’s a lot of information on line that can help one checking our career oriented psyche. Try to figure out your strength or weakness in doing translation, such as concentration, quick response, bilingual mode of thinking, etc.
When you finish this step, try to narrow down your goal. I can understand you desire to be a translator and interpreter at the same time. But it might be a little difficult to achieve these two goals at the same time, since you have realized that you have not practiced English for quite a long time. Personally, I would believe that translation is easier for you now, for you still have daily English writing practices when you reply the emails. Thus, you can concentrate your effort on translation for one to three months, and then move to the alternative practice of translation and interpretation.
When you think you are ready, have some exams, such as: National Accreditation Examinations for Translators and Interpreters (NAETI). You can start from Grade 3 and then to Grade 2. So, preparations for the exams are necessary. If your job does not occupy lots of your time, you can do some model tests at your spare time during your working hours (as long as it is allowed). And you should do regular practices on weekends. That means you are giving up your entertainment time for the exams, you can consider whether they deserve it. After you pass the exams, you can have the certificate for translation or interpretation corresponding to your English level. With these certificates, I am sure that you can find a job as a translator or interpreter more easily.
Susan, the above is my advice to you. I wish it can help you more or less!
Looking forward to your reply!
Best wishes,
Yours sincerely,
Sophia