According to the documented policy, it is OK to answer your own question, and even encouraged. Personally, I think it answering your own question is fine, and something we should encourage if both the question and answer are good ones. I don't think we should discriminate against cases where there's an answer from the person who asked the question.
However, I have had experience where I wondered if I'd been singled out for special scrutiny because I answered my own question (even though everyone gave other reasons, I still wondered), so I've drawn the inference that it is allowed but may sometimes be viewed with suspicion and may not always be encouraged. Of course, with a sample size of n=1, I would hesitate to draw too many conclusions.
Regardless of my personal experience, I have the impression that there are some people who view answering your own question with skepticism and view it as a potential sign of gaming the system (see also here and here and here), and you may see downvotes or demands to mark your question as a community wiki, regardless of the official policy, particularly if people think (rightly or wrongly) that you are just seeking rep points. People behave in all sorts of interesting ways, regardless of what the official policy may say. So, just be prepared for it and wear a thick skin.