Without knowing anything about your group besides the little you've given, here's my advice.
1. Don't sweat your character. As long as you're happy with it, that's what matters. There are some people for whom their happiness is derived at least in part from being effective in combat, and if you're in that category then by all means feel free to ask for advice on optimizing your character... But don't feel that it's a requirement. If you just care about being an eladrin who plays a lute and tells stories of great heroes, just focus on that.
It's also worth noting that it's very, very difficult to make a character for 4th edition which is really bad at combat. Even if you're completely anti-optimized, you'll still have some level of competence.
2. Depending on your group, there's a few different things that might happen.
a. If they have lots of in-jokes and references to the past... it may make you feel like you're being pushed away. Not much to be done about that except grin and bear it. That's just something that happens with established groups. Fear not, though, for it won't be long until something stupid and funny happens while you're there and you'll be privy to your first running in-joke.
b. At some point, people will probably suggest things to you, whether it be feats or powers you should take or tactics you should use in combat. This can be a bit tricky to handle... If it seems like they're just trying to offer helpful advice, and you don't mind, then take it into consideration. If you don't want their advice, politely explain that you appreciate it but you're happy playing the character as you are. If it seems like they're commanding you on what to do, politely but firmly remind them that it's your character.
c. Don't hesitate to ask questions. In fact, most DMs will absolutely love talking about their settings and if you ask a question about something they'll be happy to go on and on about it. Other players will likely be happy to offer any advice you might ask for or help you with the rules.