Don't worry about it looking weird; calling someone "Ah-[given name]"* is usually only done orally and, if in written form, only in small notes and little letters. Most importantly, it mostly only occurs in an informal context, so you won't find it on formal documents.
*The "Ah" character is usually placed before the last character of one's Chinese given name.
In China, this name is perfectly acceptable. But in other countries, it'll always be, "Ah, it's you!" or "Ah, you scared me!" It should not be used as a name outside China.
Please see the name entry as well as my own explanation. "Ah" (阿) does not exist as a name on its own. You'll never find someone called "LI Ah" (surname typed entirely in caps) in sinophone societies, for example (nor "LI Ah-Ah", in case you were wondering). LI Ah-Niu ("Niu" being "牛" [Chinese encoding possibly needed to see this character], meaning "bull/cow") could, perhaps, be the name of someone who's less well-to-do. Even among the higher income brackets, you might see - in the familial context - more senior members of the family calling the juniors (when I speak of "seniors" or "juniors", it's across generations) things like "Ah Xian" or "Ah Jing", provided the names of the juniors contain one of the characters corresponding to the respective sets of pinyin, be it "Xian" or "Jing" or whatever else.
To cut the long story short, you will *NEVER* find "Ah" (阿) existing as a standalone name, and hence the problem you speak of is nonexistent, quod erat demonstrandum.