Nauseous in the mornings?

For the past couple days, I have woken up with nausea. When I'm still laying in bed I feel fine, but once it sit up, I get nauseous. But, once I eat something, I am usually fine. Today, It was even worse and I haven't been able to eat anything. I'm taking promethazine, but I don't think it's working. What do yall think? Have you experienced similar stuff or do you think I have something or what?