Usually heavy bleeding is not due to birth control pills..
However it could be because of exertion that u had..
Or if u hv bn noncompliant with birth control pills it could be a failure rarely..
I suggest you do a urine
pregnancy test to rule out any pregnancy..
Other causes cn be hormonal issues like
thyroid disorders, Pcos , fibroids , polyps,ovarian cysts etc
Next Steps
initiate a direct consult on further detailed management