I can see that you must feel absolutely dreadful and feel like there is no end to this - I was exactly the same at that time, low everything, numerous kidney infections, in and out of hosp, it was during the big snowfall and I was stuck at home, signed off work, feeling utterly despondent. I also wasn't eating much due to heartburn/vomiting/total lack of appetite.
BUT - in the end I convinced myself I had to eat, to ensure my baby had a good chance, what I was doing wasn't fair.
Everyone thought the baby would come early but in the end she came at 39 weeks. Those final 10 weeks were the worst of my life but the minute she was born it was all forgotten and now it feels like a very dim and distant memory (DD is 18 months old).
If you have a tough pregnancy, you are consumed by it - but it really really is only a short time out of your life. If it helps, as I had such a rough time being pregnant, once she was born, I was so relieved and happy not to be pregnant any more that I flew through the first few months and found it an absolute doddle. Give me a newborn over being pregnant anyday.
Good luck and please do as your doctor/midwife directs you to (maybe taking iron supplements etc), even if it makes you feel ill - you have to put your baby first, they are relying on you.