Hi.
I'm not sure exactly why you told him you had already had sex. Maybe you thought it was nerdy to be a virgin. Or maybe you thought he would balk if he knew he had to "initiate" you. But the truth is there are many people your age who are NOT having sex. Your situation is not unusual.
Besides, there may actually be a benefit to telling your boyfriend the truth. Having sex the first time could be a physically uncomfortable experience for you, so it would be helpful for him to know he must go slowly at first and follow your cues.
It is understandable that you might have some performance anxiety, however. When you do get around to having sex, it might take some pressure off to think of it not as a performance, but as a mutual exploration in pleasure and connectedness. To make the experience even less stressful, consider protecting yourself by using condoms.