With no other symptoms like heavy voice, normal periods, no obesity, no abnormal of facial hair, this is likely to be nothing serious and PCOS is not likely. Still this can be substantiated by the insulin fasting test. So you should not be worried. Yasmin can be responsible or contribute to the hair fall. Some hair fall is normal for all the individuals including women (around 15-25 hair a day). Only when this is excessive or continuous, one needs active treatment. In females the common causes of hair loss are following;
4) scalp problems like infections, allergies
5) vitamin deficiency
6) iron deficiency
7) hypothyroidism (low thyroid functions)
9) telogen effluvium; recovery is spontaneous and typically occurs in 3-6 months
In your age group scalp local problems should be ruled out by the physical examination, by a skin specialist as the first step for the evaluation. Increase level of androgens can cause hair fall in females and the characteristic of this fall is generalized fall from whole of the scalp then the isolated area wise fall. If your fall is generalized, you may consider consulting an endocrinologist. Meanwhile start vitamins and iron supplements. If needed, you may continue using, Minoxidil, which may help hair to grow.
Please feel free for your follow up questions.