SEVERE Morning Sickness (lasts all day, weak and lethargic)

I am having the worst morning sickness! Today I had dry corn flakes, and a baked potato with butter and s&p. Couldn't hold it down. Sometimes I even throw up water. It's making me feel like I'm going to pass out and I've been so weak I've called out from work. Just started this weekend. I'm 10 weeks and 4 days. Anyone else dealing with this? What's the best thing to do? Worried baby isn't getting enough and I need energy, can't keep missing work.