Yes, you have a beautiful baby boy and it's wonderful - congratulations. Saying that you are disappointed about the 'birth' does not make you ungrateful! You just wanted to have a different birth experience.
I am not sure if your hospital offer a birth debrief service, but i believe that PANDA do. I think there are many women who struggle after a c/s. I am still unable to say my DS2 was 'born', so I know what you mean. (we had ours at nearly the same time ) My DH wants me to seek professional help, but i have not been courageous enough to take that step yet.
As for what to do next time - I think you shouldn't worry just yet. I think that if you prepare yourself well, then if you plan a vbac, and eventually need a c/s - you will not be messed up, because you can already work through some of those feelings before hand.
Good on you for admitting how you feel, and speaking about it. I hope you can process your feelings and get some resolution.
I haven't helped much, but i wanted to let you know that you are not alone.
Jo