What should i do about my brother?

i'm 15 years old male and just came out to my dad as gay and he is in the navy so he doesn't want to have a as a sn and kicked me out.i started to live with my 25 year old sister in-law and her daughter my brother is on a business trip and he hates me since we were young,when he got back i told him what happened and he told me:"just don't do something you'll regret" i started to date a boy in my school and he is 17 years old and in the football team and he is in the closet and he is very possessive.when my brother found out he told me i shouldn't see him any more and that he is too old for me and now suddenly he wants to meet him and started to act like a parent in the past he didn't care about me and now suddenly he is acting like this.i know i sound paranoid but this is just too much what should i do?