First contact... now what?

I would like to say 'hi!' this is my first time here. I found my daughter and son I gave up for adoption on facebook recently. She replied right away when she realized who I was. We haven't actually talked. But she gave my info to her brother and he called me right away. I have had so many different emotions since then and really need advice on how to further our 'relationship'. He did say he wanted to continue contact and he politely asked how I felt about this. I do also, of course! I feel so weird, nervous and anxious about even sending a text to say 'hi'. I feel like a girlfriend not wanting to make a wrong move. Kinda gross but I can't related these feelings to anything else. I want to be able to talk to him and not dwell on the past, but learn about his life now. But it seems so strange though and I'm not sure how to; because we are strangers. Any advice is appreciated. We do not live close to each other so meeting in person (which I would prefer) will have to wait. I'd really like to try and make a 'connection' but I don't really know how to. God I sound lame :/