nausea worst ever today... scared

My nausea has been the worst and I've thrown up 4 times today! In my first trimester in the worst of the sickness I was throwing up like 4-6x in the whole week! What I've eaten today is mainly oatmeal, bread, crackers, bananas, a apple, and water. To make my day worse I woke up with a headache that hasn't gone away. I'm 17 weeks and probably just need to start taking my unisom again. Part of me is worried it might be something else. Currently in bed 😔