Metformin help

I was diagnosed with PCOS after a year of ttc. My doctor prescribed metformin and wanted me to increase from 500mg to 1000 after a couple of weeks. I did but it was making me sick as in light-headed and nauseous. So I backed back down to 500. Except that hasn't helped me any with regulating my period.

So here's my question. Can I split the dose? Can I take 500 with my first meal of the day and a second with my last? Will that help with the nausea and lightheadedness and be enough to regulate my period? I do have an appointment set up for the 5th of December to talk to my doctor but it isn't for two more weeks.