Hi. Thanks for your query. Noted the history of constant cramps in lower stomach, back ache, slight constipation, trouble having bowel movements, tender breasts, fainting on standing up, nausea and shortness of breath on walking or laying down on back. Period is due in 2 days so PMS is ruled off and has been getting worse in past few days... Such a symptom complex can occur due to many reasons: This indeed can be due to Pre-menstrual syndrome. If there is no relief with the routine symptomatic treatment with antispasmodics and analgesics, this goes in favor of PMS. I would advise you the following: Consult your Gynecologist as on clinical evaluation She can know whether this is PMS or not; if not get a referral for a General Surgeon for clinical evaluation and examination and further investigations like ultrasound, tests of blood, stool and urine. This will give an idea about the clinical diagnosis and helps to have a plan for the complete relief. Tests for thyroid can also be helpful as well as any community disease going in your area as your Doctor would know the best. Take care to get a proper diagnosis so that a proper treatment can be done.