Yeah I Have An Irregular Period All The Time I

Yeah I have an irregular period all the time I usually skip a month then have a period. But I haven't had a period since the middle of October. Didn't have one in November or December. I took a pregnancy test on the 22nd of December and it came back negative. This is the 7th of January and still no sign of a period. What could be going on? I feel pregnant but the test showed I wasn't .