What Causes Sweaty Feet And Hands?

I was diagnosed with hypothyroidism (on two hormones) about 5 year ago. Then vertigo about two years ago. Now I get sweaty feet and hands most of the time when I leave the house. Especially if I know that walking stairs or hills will be involved. I also have a hard time sleeping, I used to be a champion sleeper. My brother died in December and the symptoms are getting worse. Also, I was diagnosed with mild seizure disorder, I taking gabapentin nightly. Is this anxiety?