Using the initial for the surname may actually be more distracting for the reader, because it seems like a deliberate attempt at hiding identity, such as is done when writing tell-all books about some long-held secret. It also makes it harder for reviewers and commenters to refer to you by surname; some will end up finding out your real name and using that, and that will create confusion among your readers. And a single letter alone will make it harder to find you in online searches.
You might consider a short and catchy variant of your real name, like "Ana Nov" or "Ana Nova". Or, as others have said, your middle name, or some name in your family that has a nice ring to it and (very important) will be unique when people search for you.
I'm also given to understand that in many cases, pen-names (and stage-names) have arisen from the suggestion of publishers or agents, who may have a good sense for the market you hope to reach. So you might consider submitting your first manuscripts with your full name, and asking for feedback at that time.
Though, having suggested it, I will say that "Ana Nova" has a nice ring to it.