AKID- I know how you feel. AS Scratchme said " some JW's are very inappropriate and intrusive " and as On The Way Out said " Many elders ( or any JW for that matter ) ( Italics mine ) think they can cross boundaries that are really innappropriate . "
I agree with both these statements as I used to experience this intrusion into my personal space when I was your age growing up as a JW. And I've still experienced this treatment from JW's even into my middle age years up till now still. And I'm in my 50's ! And I'm an EX-JW !
It sounds definitely like this " brother " was trying to put you on the spot about girls in front of others to test you. Or he was trying to get some dirt on you in front of others to embarrass you. Or use information you gave out against you later by blabbing to elders about your personal life- which is none of his business.
One thing adult JW's will try to do to teenagers or minors is control them by asking intrusive questions which are none of their business. You just have to stand up to these people in a firm, yet dignified polite way and say, " excuse me, but this is my personal business and not yours " - then walk away. In the JW's anything we say can or will be held against us by unscrupulous fellow JW's with bad motives trying to either get us in trouble with our parents or elders. As On The Way Out stated, " These people are not going to be your friends in the future, so screw them. " Which I agree with.
If you can develop friendships with non-JW's who accept you for who you are- not JW's who want to mold you into something or someone that you don't want to be . Hang in there buddy, we're here for you too. Take care, Peace out, Mr. Flipper