Wow.. hopefully everything falls into place for you. I can only imagine your feelings right about now. That is really neat. I also have to tell you I am 20 yrs old as well and my parents are older.. my mom is 62 but I have 4 older brothers and they are in their 40's. Definitely not the same relationship that my friends had with their brothers but at an older age it gets better. When I was little they disciplined me and I grew up with their kids so I have nieces and nephews younger then me. In fact, Im a great aunt already haha so it is very different but it might be fun. Its always interesting trying to explain it to people.
I am very happy for you! I know this may seem like an ending (having finally found him) but it is really only a beginning. Relationships take time and effort from both parties to become strong and healthy. And remember, as someone said before, if this doesn't work out the way you hope, don't let it effect the person you are. We are much more than the genes we were born with. Also, it seems like your birthmother has done at least one positive thing for you by giving him your contact info? Best of luck to you!