What Causes Extreme Hot Flashes Along With Dizzy Spells Post Hysterectomy?

I have been going through extreme hotflashes lately. I am 44 yr old female and have had a partial hysterectomy. When I woke this morning it felt like I had been pushed back on the bed. I laid back and when I got up again it felt like someone flipped my mattress and i was falling. Today at work I felt like I was going to fall over. All these passed quite quick but left me feeling quite dizzy. What could this be from?