Hi I have gone through your query, i will try to give you suggestion which will be helpful to you.  If you had unprotected sex and you re period is delayed. Then one should rule out pregnancy first. I would suggest you to do urine pregnancy test with morning sample of urine, which is found to be more sensitive. It should be fine at least a week after missed period. Menstrual irregularities are seen with thyroid disorder but pregnancy should be ruled out. This provisional advice provided by me is based entirely on the input provided to me. I would suggest examination by the doctor. I hope this suggestion might be of some help to you. I will be glad to help you in case if you have any further queries. Wish you speedy recovery. Take care.