Yes, you have the right to represent yourself in a criminal case. A judge must first determine you legally competent. As long as you are determined to be legally competent, give up the right to an attorney, and understand the court proceedings, you are entitled to represent yourself.
There are several reasons why we would not suggest you represent yourself and instead hire a criminal defense attorney. This includes: lack of courtroom experience, you may make self-incriminating statements, and you may not understand court rules.