Hello Sameer, 

BC-E is definitely a sub division under the OBC category and you are allowed 4% reservation. However for many centralized exams and jobs, they do not accept the BC-E certificate only, and will ask for a central OBC certificate. You can get such a certificate at your nearby Tehsil/District Collector's office. Fill and submit the form issued by them and you should get your central OBC certificate within 10 days. 

Hope this helps. :)