It would be a good idea to take a pregnancy test just in case. However, if you had very heavy periods for a day and didn't miscarry, it would be unlikely.
It happens under severe stress that the menstrual cycle shuts down and you can be a while without menses. When the severe stress stops, the cycle returns to normal after a few months.
In some cases, the body needs a bit of help getting back to normal. Vitex from A.Vogel can help in those situations, but only if you are not pregnant!
Another possibility is early menopause, in which case I would also recommend Vitex from A.Vogel. It would eliminate the risk of going through early menopause because of excess stress.
Premature menopause can lead to higher risks of osteoporosis and heart problems.