Thanks for you query.
I read your query and I understand your concerns.
Following is my reply:
1) The delay in your cycles once in a while is normal and not to be worried.
2) Lot of causes like obesity, stress
etc cause variation in cycles .Dont worry
I hope I answered your query. I will be available for any follow up query you have.
Dr. Mahesh Koregol
IVF & Infertility