I make films. But I have never made any money making films, so I usually say I "make films" rather than refer to myself as a "filmmaker". At the end of the day it's all semantics, but here's my two cents anyway:
You may be a maker of films if:
1. Your friends introduce you to people by saying that you "make films".
2. You have looked up the spelling of the word "filmmaker" for your CV.
3. You talk about your "production company" that doesn't actually exist.
4. You use the pronoun "we" when actually you have written, directed and edited your film by yourself.*
5. You can be heard at parties declaring loudly "I am a filmmaker".*
*If both numbers 4 and 5 apply, there is strong possibility you are not only "a maker of films" but also an "auteur".
You are probably a filmmaker if:
1. You aren't sure if "filmmaker" is one word, two words or has a hyphen somewhere in it and aren't really bothered about it.
2. Your account with your post production facility has been sent to a collections agency.
3. You refer to "capturing" data in Final Cut as "digitizing".
4. You are so busy making films that you rarely have time to watch any.
5. You don't care whether people call you a "maker a films" or a "filmmaker". You just want to make films.