i'll be 14 weeks in a couple of days and I had the same problem until I was about 11-12 weeks. I'm surprised since you can't hold anything down your doctor didn't offer you some kind of medication. Diclectin and Zofran (i think thats how you spell it) are completely safe during pregnancy and help alot with nausea, especially if you can't eat.
I know for me the thought of food at all made me feel ill. I found taking my prenatal at night helped alot (you don't mention when your taking it now), and also popsicles! I would always get sick in the car on the way to work so i'd grab a popsicles on the way out and it helped alot.
Also I found the longer I went without eating (especially when i felt sick), the more sick I would feel later on, if that makes sense. It just turned into a cycle of not feeling like i could eat for days which seemed to compound the sickness. when I did force myself to eat small meals throughout the day my sickness seemed to lessen (altough I was obviously still nauseaus and not enjoying the eating) Try to eat at least something, maybe some saltine crackers or toast, something to have in your stomach.