I experience a feeling of evil with in myself. I have a history of mental illness. But now I feel better, I try to be good. But I always have this feeling that there is a true evil dwelling within me. I also have had an experience of not being able to control my movement. Like the moving of the head in a circular motion. Do you think that it is the Satan? And what can I do?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

First, of all we ask Allaah to cure you and to greatly reward you for being patient through this affliction. The symptoms that you feel could be due to a physical disease or stress, so you have to consult the trustworthy doctors specialised in the field. This could also be caused by evil eye, magic, or an attack by a Jinn, etc. Therefore, you have to seek Ruqyah from the Book of Allaah and the Sunnah of the Prophet . There is no harm in this regard in seeking the help of someone who is known to be righteous, and in accordance with religious requirements, like having a Mahram (non-marriageable relative) present, wearing Hijab, and so forth. Most importantly in your cure is to be steadfast in obeying Allaah and avoiding His wrath. You should also supplicate as much as possible, especially in the times and ways in which the supplication is most likely to be accepted by Allaah, like when being in prostration, in the last third of the night, and so on. 

Allaah knows best.