So I normally have an irregular period but recently my period has been a little bit more a irregular then normal lately.

Two months ago I did not get my period for a whole month and a half. I found out my best friend was pregnant and due to being with and around her every day my period stopped with hers for awhile until my body realized what was goin on. Since then I got my period again twice. Now I’m eight days late on what should be my current period time. Even with the irregularities in my period I always get it between the 1st and the 10th every month so now Idk what the interruption is?? I took a pregnancy test and it’s negative so what could it be now??