Should I be concerned?!

Mercedes
Tmi at times!
 but today's the first day I've ever had morning sickeness, I'm 10 weeks. And 
When I got sick my puke was yellow.. Like macaroni and cheese yellow, I didn't think anything about it because that's what I ate last night before bed, well  I just urineated and it was the same color! 
I feel sorta light headed.. And I know I haven drank enough water... Is it just dehydration or could it be something worse?