i just need advice i guess (trigger warning) sorry for all the grammar mistakes

So I am 15 and safe but when I was younger I was sexually abused by my stepfather. I don't remember when it started but now he's in jail because I finally told my mother. I was so scared that she wouldn't believe me but when I told her she believed me. I'm happy that I told her because now I'm safe and far away from him. But the thing is the aftermath. as of right now I go to therapy every once a week and at first, I didn't like it because I was scared to say anything and I still am scared. I started to self-harm at the end of freshmen year because whenever I did something wrong I deserve to be punished or when I get super angry or when I have thoughts about wanting to end things. (i know that sounds crazy.) . my therapist knew I had depression but she didn't know how bad it was until we had a session together and I hesitated on a question. so when I told her about my thoughts she brought in my mother to discuss a plan. but the thing is that when they asked me if I self-harmed I got nervous and said no and I am the type of person who hates lying. and now I don't know what to do. should I tell my therapist I lied and tell her that i self-harm or????