Hello and welcome to HCM,Oral contraceptive pills
act by suspending the ovulation during the time when it is used.
After stopping the pills, ovulation takes some time to re-start.
Regular periods take around 6 months to resume.
During this period, the cycles may be irregular and ovulation may be suspended.
The time taken to resume periods varies from woman to woman.Pregnancy
is ruled out since the pregnancy test is negative.
Cramps and headache may be unrelated to the menstrual cycles and they are not signs of pregnancy.
Thanks and take care
Dr Shailja P Wahal