Thanks for your query
What you are suffering from is called post pill amenorrhoea.
Sometimes, it lasts for upto 3 - 6 months after continuous use of oral contraceptive pills
But its already been almost 6 months, so you should definitely opt for some treatment now, particularly if desirous for children.
you have not mentioned your age, please let me know that.
Also, the rebound weight gain is also common after stopping the pills.
You need to get your hormonal
tests such as estrogen, progesterone
, FSH, LH, etc , if required endometrial biopsy
etc to know the cause of absent periods.