What Causes Hot Flashes On Cheek?

I am 30/F...recently put on Synthroid/Metformin (low dose) for diabetes and lexapro. I have never been on any medications before, and for the past 3 months I've had to take all 3. I keep having hot "flashes" on my left cheek, and the rest of my body seems fine. It's really starting to be an irritation.