Thanks for posting your query on health care magic.
Flow of as low as one day is still considered to be normal.
Such chances are due to hormonal
imbalance in the body.
Nothing needs to be done.
Your periods will be back as before in about 3 months.
If the problem persists, i suggest you to get a ultrasound
done for endometrial thickness.
If endometrial thickness is less than 4mm, you need to take estrogen
supplements for endometrial growth.
Hope this helps.