Strange Happenings!!

Hello gals,
Have a strange problem.. hope someone will point me in the right direction!
My mother-in-law was bedridden from December 2015 till last month (she passed on July 13th) .. I was at native looking after her and hubby was at his city of work.. (son was with my parents.. long story!!!) I was with in-laws from January.. till march things were ok.. my menses were regular.. 3 days normal.. from April it started.. I had on time.. but flow only second day ( dark red color).. rest days maximum a few drops and had bad cramping in the abdomen.. the day she passed.. I got my periods.. though was painful had as usual flow like before December (three days full red color).. and this month it's one week early.. why was it one day only 4 months and so much painful?? Thyroid test was done which was normal.. scan was supposed to be in July as things turned normal..

Can anyone please tell me what be the reason..?? Stress may be .. but now the jump to week before is not usual for me so far!