Will Allah forgive me for this?

I am a girl, age of 13 and I have been crying a lot and I've been so worried. I am learning how to perform the 2 Raka'at (2 units) and 4 Raka'at. I have also been lying a lot and I am starting to repent and turn to Allah. I have been worried so much, I've been crying for a long time. Am I allowed to pray in order to forgive my sins? Please answer, I am so worried. I told my mum that I was afraid of going to hell and I've been crying so much. I also learnt about how you must not hurt Allah's servants, and that you must apologise and ask for forgiveness. If they say no, Allah can not forgive you. However, when I was about 3-5 years old, I slapped a young child because he was in my way and I deeply regret my actions. Does the sin count, and can Allah still forgive me? I regret all the sins I have committed and I worry about this all the time. Please someone answer me, I do not want to go to hell. Please inshallah I really want to go to heaven.