Cheating?

I have a question

My younger brother is actually better chess player than me. he is just 17 years old. Funny thing is that he used to take my laptop several times without me knowing. I told him stop using my account and create one for himself. I have a password now on my laptop and he has his own account, he won some games ,but yet he lost some, so i do not justify what he has done to me , so yea i will keep playing till i get better rating than him and beat him one day. i dont know if those games count as cheating cuz he is better than me and i obv did not know he used my account sometimes. I am scared that chess.com might view those games as cheating or unfair play and just close my account. he is obv better than me so those games might look like i was cheating. cheating is unfair obv. 

Anyone of the fair play team here?

Questions about cheating aren't allowed in the forums. You can ask them in the Cheating Forum, which is a club you can join. I don't know the answer and I don't think anyone from the Fair Play team will likely answer directly. However, some people with a fair amount of experience participate there and they may have opinions on your question.

It seems to me that you have taken one step to try to remedy the situation going forward. However, you should also change your Chess.com password, since your brother could log in from any other computer. (You can do that in settings.)