Light headed 🥴

I am currently 10 weeks and 1 day this is pregnancy number 4 for me and I’ve never experienced anything like this with my other babies so they saying every pregnancy is different is hitting me real hard. I never had morning sickness but with this baby I am sick all day everyday not able to keep anything down or really want anything. At this point I am forcing myself to eat but I still get sick. I have lost 10 pounds since being pregnant and I had a appointment yesterday and my doctor told me the ketones in my urine were high. I am so light headed and dizzy at work all day most likely from eating very little and I feel extremely hot and sometimes like I need to sit down before I pass out. Has anyone had this problem and what are so better ways I can deal with this? My doctor gave me zofran so hopefully that helps and I can start eating and feel a little better.