Can you get a wonky LP cycle? TMI

frogyie

This is my 3rd cycle since my D&C. ..Last month I didn't chart but I got AF about 11 dpo dependent on OPKs. 

Although this is my first cycle charting it is crazy... tomorrow is DPO15 and my longes cycle has been 38 days but since my M/C it has been around 30-34 days.... I have this brown spotting for a couple of days now that comes and goes (only when I wipe) but my temp didn't really drop this morning... I am refusing to take another HPT until saturday but I was just wondering if something is wrong with me.    I know you cycles can change because your O date varies but I thought the LP should be only a day or so different.  Sorry if this is a real newbie question