May reflects your concern about potential disappointments.
Issues with unfinished personal matters.
Having a dream with snakes biting you in your back has several interpretations:
The first and most common meaning indicates that this dream reflects your concern about potential betrayals or disappointments in your current relationships with your partner, family, business, or at your office. Likewise, this dream may be expressing your belief that something intimate, or very personal might be revealed to others.
The second, and the less common interpretation, means problems or concerns with outstanding issues of the past that may be still affecting you. It is possible that you may have been forgotten them, but this dream may be showing you that they are still alive and becoming a heavy emotional burden. Examples of this issues: relationships or personals conflicts that have a long time.
Third one, in some cases dreaming that snakes, boas or vipers that bite on your back may mean that there are problems with the dreamer’s personal responsibilities or obligations.
Finally, the fourth interpretation, this dream can symbolize a sudden setback in an area of your life to which you were not paying enough attention. Also, it may refer to a personal issue happing when you are not prepared, or when nobody did not see that coming.