No. An unrepentant person can feel bad or sorry about doing something sinful, but there will be no lasting change. Consider the abusive husband that cries and tells his wife he is sorry after abusing her in a drunken rage. That sorrow only lasts until he gets drunk again, and the story is repeated. This is the sorrow of the world. Godly sorrow (2 Corinthians 7:10) is that which galvanizes the sinner to change no matter what the price. When someone is under conviction of the Holy Spirit they might feel bad and even cry because they know they are living in sin. However, tears or feelings of regret are not sufficient. There must be sorrow of a godly sort due to the recognition of wrongdoing accompanied with a purpose never to return to that life of sin. This is the only kind of sorrow that will bring true repentance.