I "think" I can relate to how you feel AmericanEIT....at least if you are the only structural engineer.
I work at a company where I'm the only structural engineer. I've been out of school for about 5 months now (I'm also finishing a Masters in Structural Engr....only 2/3 of my thesis left). When I first started, way back in the day

, I felt as though I had learned little in my schooling, especially reading the posts on this site. Now after being out a few months and talking to the other (non-structural) engineers I work with, I realize how much more I know about structures than they do. I just take it for granted!!
I also realize that my learning curve will be rather steep w/o having a structural engineering "mentor". I use my major professor from my masters and this forum for ALOT of professional insight.
If I wouldn't have went on to (almost) get my Master's I can only imagine how much further behind I would be. If you are the only structural engineer in the firm then, in my estimation, what you feel is normal. The learning curve is steeper but that just means we need work a little harder to keep up.
As dlew indicated, it all really comes down to confidence in yourself. The key is to NEVER stop learning!!
Carpe Diem!!