Hi,
The description of your level of anxiety, sounds a lot like unresolved issues with the past sexual experience you had at 14. Please don't beat yourself up or feel guilty because of the choices you've made in the past. Fourteen is very young, and you were unprepared for what took place between you and the 20 year old adult...
Unless you have already sought counseling, I suggest that you seek advice and treatment from a therapist before you continue with any sexual intimacy. Speaking with a therapist can give you an outlet for you to talk about how you feel, and it can teach you how to work through any guilt or shame that you've been dealing with. It is up to you to decide on what you are most comfortable with; if you don't feel at ease right now with having sex in your current relationship, don't do it. Don't leave your partner in the dark ~ when you can, you should talk with your partner about your feelings on all of this, so that he will understand where you are coming from emotionally and physically. If he truly cares about you, he will be understanding and sympathetic to your needs...
The California legal age of consent for sexual contact is 18 years old; it varies with different jurisdictions, in different states. There are exceptions that you may want to read about in the 'Romeo & Juliet Law', which you can research online, or at a library. It can supply you with more information in regard to your question about sexual abuse...
I hope this helped some :)
Good Luck