On the basis of your sign and symptom you can be a patient of irregular period ( abnormal period) due to stress, anxiety, anorexia , weakness and poly cystic ovarian disease etc.
But what is the exact reason to find out it you should take consultation from a doctor to make correct diagnosis .
Next Steps
You should do some test according to doctor after taking consultation.
Health Tips
Don't worry your period will become regular.
please keep positive attitude.