Feeling connected and a sense of supporting community is really important to be happy with the work you are doing. I found that sense of community by making a friend at work, someone that I would hang with outside of work and could relate and support me in decisions. This friend also pushes me and we have some fun competitions sometimes to better our skills that we use for work or to learn new ones. I have since looked to make friends in more co-workers to build my community and network of people that give me this feeling and that I hopefully provide for them too!
I know this part sounds cliche and old but if there is no luck with co-workers or even friends then there is always the community you are talking to here! HN is a great way to improve and become active in community. HN is not the only one too, meetups around your area could be more common than you think. Take the time to get out and meet other people in your field and take it upon yourself to expand your network and community.
Overall I would say keep up drive for new experiences and career building. You might even try to suggest ways to improve and build community within your company! Take it upon yourself to see if you can push the company to implement your ideas! :)
One thing I was able to do recently that gave me a good perspective is attend a conference (CodeMash). I was able to talk to many people and see a few talks which was a great experience.
I'd say out of the building I'm in I'm one of the youngest working here (that I know of).
The company culture isn't stuffy - I can essentially come and go as long as I get my stuff done that I need to. I wish it was less bureaucratic and "office like", but I think we're growing away from that.
Tech wise - the .NET stack has grown on me in the time I've been here, but I still worry that I'll only be exposed to languages I'm forced to use at work as opposed to languages and technologies I want to use/learn.
Everyone I work with is great as well, but the one thing I miss about college/small college town is the community/connected feeling. I don't get that feeling at all currently, so I'm trying to pinpoint why I'm not feeling that anymore.