body issues in first trimester

So I'm 9 weeks and 1 day and my diet is all over the place. Some days I'm perfectly fine and can eat my usual healthy meals (I was doing slimming world before). But most days I can only eat plain stuff including things like waffles, hash browns and chips. I never ate frozen or processed food before. I'm also snacking more often to battle nausea and dizziness. I'm snacking on crackers and rice cakes but I'm piling on the weight (or it feels that way). My metabolism isn't the best. We are so thrilled to be pregnant but I feel like my body's out of my control. My midwife said the most important thing is that I'm eating not necessarily what. Does anyone feel the same?