For four months my menstrual cycle has been weird. i have been cramping more and throughout my period which never happens and after my cycle ends i get constipated and have bad gas. ?

Seek medical consult: What you describe may (or may not) be serious. You should seek medical consultation right away, so that a doctor can get more information about this, and advise you appropriately. HealthTap video and text+pictures consultations are available; just start over and click on Talk-to-Doctor. Or, call your doctor's office. I hope you feel better soon!