merlinextralight speaks the truth. If any of us were gamblers, I don't think we'd bet that you were going to ever be a pro cyclist.

That doesn't mean you should be discouraged, though. Not becoming a pro cyclist doesn't make you a failure unless you set an unrealistic goal.

Follow merlin's advice and see how it goes. Try a couple races and see if you even like it. Then, when/if you're a Cat 5, loving it, and doing well, look to upgrade. And if, years down the line, you work your way up to Cat 1 and you're putting in some strong results, then I'm guessing that the necessary people will take notice (although I'm 100% unfamiliar with the process).

Set some realistic goals, like "don't get shot out the back in my first race," and just have fun. Statistically, if you do all your riding with the idea that you're going to become a pro, I can almost guarantee you're in for some serious disappointment.