How old was I when I gave my 1st BJ

Ok so I was like coerced into doing it by my older mid teen brother as we watched online porn on his laptop in his room while our mom was out shopping and we were alone together in the house when I was almost ten years old. I know, I know, I shouldn't have but looking at those vids then actually seeing my brother's erection just got me aroused enough that even though he did coerce me and I did hesitate, I did give in and did it. I was like Eeew with the first few but sort of just copied the vid we looked at. So like he wanted more but I only agreed to anal sex. Holy cow did that hurt, I barely tolerated it, thank goodness he finished in me really quick and pulled it out. THEN we heard the van crunching into the driveway and I ran to my room pulling up my jeans. EXTREMELY close call with getting caught. I never ever, ever did anything with him again. It's like it never happened but I know he remembers it as much as I do but we do NOT talk about it and I have to admit to masturbating a few times immediately after that incident while thinking about it but a sense of profound shame has replaced those horny thoughts when I was a little girl.