I'm confused??

Amber • Hopeful ☺️
  Soooo until this past year I haven't had a regular period. It had a mind of its own. However for about the past year maybe a little longer, my periods have been pretty regular. 
  Well in October I had two periods. One the first week of the month, and the second came on the last week of the month. Both were normal 4 day periods. I haven't had a period since. I took a pregnancy test a few moments ago and it was negative.  I have no health issues. And even though my periods before were never regular, I never just not had a period.... Can someone give me a little help or some answers?