I found this list of Top Ten Ways You Know You’re a Writer at the blog of Kasie West, fellow future published author. Sadly, all of them applied. These were the top 3 for me, though.
6- You are rejected more now than you ever were in high school.
5- Your daily mood is directly correlated to your daily word count.
3- You spend more time with your imaginary friends than with your real ones (and you’re perfectly fine with that).