That's the spirit. You are only really limited by what you think or don't think you can do. Often what you believe about yourself is far more real to you then reality. So a lot about cycling is really about what you truely think you can accomplish not what others think.

I rode my first century 2 years ago in May. In April I had done a 50 mile ride. The Saturday before I did a 55 mile ride with 3 monster hills and a few smaller ones. Anything but flat is the point. The next week I went out and road my first century solo, no support. But then I don't ride to feel all comfortable and happy when I am done. I ride to feel spent and looking for a 12 hour nap. I usually ride not for comfort but speed and the thrill of going fast under my own power.