Am not pregnant What medication can I take for my...

Delayed period :
First of all you have to exclude pregnancy as it's the most common cause for delayed period in your condition . If pregnancy tests were negative your doctor will prescribe medication such as Cidolut nor twice daily for 3 weeks and follow up your condition .
What are the causes of menstrual cycle delay ?

• Pregnancy 
• Stress amd Anxiety
• Hormonal disturbance
• PCO polycystic ovary
• Thyroid dysfunction
• Pelvic inflammatory diseases
• Hypothyroidism 
• High prolactine

What are the required medical tests ?
Clinical assessment and Urine pregnancy test if your period was delayed ot Blood Hcg level and US Abdomen for pregncny anc PCOs . Your doctor will order FSH , LH and TSH And Prolactine for thyroid disorders and Hyperprolactinemia .