Testing and developing are essentially the same in my opinion. Of course, a main difference is that you had to learn a programming language in order to develop. However, there are many side things you have to learn in testing also that you would not learn in development. From developing on the same product for a length of time, you become an expert with that product or at least the part of the product that you developed on. In testing, it also would depend on what you would be testing. But, from my experience, you must become a more "jack of all trades". You use more tools / utilities and learn about more of the product(s) at times than developers because you are viewing things from the customer point of view, not the creator point of view. But, in the end, for both development and testing, you have to be able to solve a problem. That is how they essentially are the same thing.
In development you are going to create. In testing you are going to try and break the creation. That is also a major difference. But, in order to break the code, you must understand how it works so that you can brainstorm how to break it. I have been on both sides of this as I was a developer but am now a tester. In the end, it is just one set of problems to solve versus the other. I am sure you will do fine.
