You are NOT too old, buddy!
I started with 20 my PPL, but stopped there. At 27 could finally 'continue', and did everything, incl. instructor, etc., even seaplane! Now I am a full ATP, and flying B737, and I am becoming 31 this year. Most of the time, nobody cares if you are around the 30s. A friend of mine, he got the same job as I do, and he is 42! And we are with our current 737 job since Sept. '08. And seriously, nobody ever gave us negative points because of our age. So, don't worry too much. Even if there will be some 'smart' guys/companies, saying you are too old, ... but life wise, correct decision making, etc., comes with maturity, something that most companies really want, you are better off then a 17 year old boy (And no offense against those young teens, ...)
And that is not my opinion, but what I have seen. Then, some companies just want some kids, to push them around.
And if you are F/O, and your Captain is 10 years younger, don't worry; he is a captain because he deserved it, because he knows his stuff, etc., forget the age thing.
Don't worry, you are at good age!