Metformin and late period....

So i was put on metformin about 2 weeks ago. They suspect pcos but cant give me a real diagnosis because i do not have many of tje symptoms besides hormone imbalance which i was told was pretty mild. I do not have insulin resistance and my cycles are pretty regular 36 days exactly every month. The metformin was given to help regulate hormones and lower testosterone and to help possibly shorten my cycles. Well my period is late and normally i would have spotted for two days before period and nothing not even a drop. So my question is will metformin delay my period? It seems like it should have the opposite effect if anything. Also i did take an hpt it was neg however i would have only been 10 dpo. Any thoughts or expierences would be appreciated! Thanks!