Light flow

So my period is every 25-27 days... I was every 28-32 days so AF has been starting like 3 days to a week early since December... so my period started on the 23 which was 3 days early and I had no signs no cramps no sore boobs nothing. And it’s been light like I put in a super tampon and went to work few hours go by and there was enough blood for a regular tampon ... last night put a pad on slept all night woke up and barely nothing on it ... I’m not under stress .. weight hasn’t changed, not on birth control and I took a pregnancy test and not pregnant.... sooooo what the heck ... why so light ... literally I put a regular tampon in this morning and just changed it ... hardly anything... idk just confused