Is it normal to do what i do

I am a boy When I was 15 I shared a room with my brother and he went away a lot so I asked my sister if she wanted to watch a movie in my bedroom and sleep in his bed. I use to creep over to his bed where she was sleepin and try puttin my hand down her bra to feel her tits/nipples and then I used to get a hard on and try puttin my dick in her mouth soo she would give me a blowjob and as I was doing that she woke up with my dick in her mouth she was shoked but she was also really horny and carried on giving me a blowjob but we never do anything more than that but I have fingerd her is it normal?