It's the reverse; we created god, and are still learning about our creation. But, you ask a scientific question about a non-scientific subject. When looking at data, science never stops asking questions. Even when coming up with a satisfying answer to one question, there are plenty more that spring up from that answer. So it makes sense for a scientist to ask who created god.
From a religious perspective, however, saying god has always been there is a satisfactory conclusion. Holy books rarely, if ever, encourage followers to seek further answers. They teach them to be complacent with one answer, and shut out all others. I'm not saying that as an insult to the followers of religion, who are mostly rational people. Rather, it's the reason that your question can't be answered by those who claim god's existence.