Thanks for your query.
It appears as if this is your normal period.
OFten, mild irregularity of menstrual cycles is common.
As your HPT was negative, there is no cause for worry.
If this becomes the routine ( irregular cycles ) - then conditions like hypothyroidism
, polycystic ovaries
, endometrial hyperplasia
etc should be ruled out.
This would require a visit to a gynecologist.
, weight gain - needless to say, could also be responsible.