Sex before marriage is absolutely wrong. It is like a man giving you a ''black mamba'' wrapped in a beautiful gift box with flowers and the works on your birthday. All he is trying to do is to steal your birthright.
Spiritually, when you engage in premarital sex you open up a wide door for demon infestation and control. You find out after the first time that certain trends will begin creep up and manifest in your life, unpleasant things that you cannot control.
The result normally is a shameful end.
But you know, the opposite of shame is glory, and that is what the Lord will replace the shame in your life if you turn to him.
Good luck.