It could be anxiety alone or anxiety caused by a bit of depression, which leads to insecurity. Is there anyone you've talked to or could talk to who you trust to help you with that traumatic experience? Was it truly traumatic, or just to you? Generally, if you're aware of why you're feeling this way it should pass as you get used to what happened -- time heals all and all that -- but sometimes we hold onto things. That can lead to chronic problems, so if that's what you think is happening, it wouldn't hurt to discuss it with your parents or an older friend or relative or a counselor of some kind.