I forgot to take my metfromin for 2 days then took it2 days later i start having light spotting i had my period 2 weeks ago already could this be because of the metformin?

It's possible but almost certainly something unrelated. Spotting is typically normal, and you might have just made the connection in your head.

The only way I can possible see any vaginal bleeding occurring is a long shot, and it would be that Metformin acts by activating AMPK which plays a role in muscle blood flow and contraction, and the increasingly vascular uterine smooth muscle during mid-cycle might be cramping to the increase in AMP. This is a huge completely unlikely stretch...

You never stated your age, but considering the fact that Metformin is used to treat type II Diabetes. Patients with type II diabetes tend to be either overweight or older adults, so spotting could indicate that menopause might be on the horizon, since both obesity and age predispose a woman for menopause.