If this were not so serious, I would be congratulating you on such a great weight loss...but as you mentioned this is a little fast. Have you spoken to your surgeon?
A lot of ways to get in protien even on liquids. I don't think I could stomach anything for about 5 weeks and those protien shakes made me gag too. Staying hydrated is the most important thing, next - as feedyoureye stated, you must treat protien as medicine and get some in. Think of your body without nutrients. Not good for your health. You did not mention if you are taking Vitamins in any form?
If you can handle milk, get some sugarfree carnation instant Breakfast shakes stir in with milk. I also used ISOPURE clear protien shakes from GNC ($4 a bottle) with 40 grams of protien. My favorite flavor is apple melon - sort of like a green jolly rancher. Getting even one of those a day in will make you feel a whole lot better.
At one point from not getting in enough carbs or Protein, I started to get very weak and tired. Another member was having same issue and her surgeon said, eat some ice cream. I went out and bought the tiny single portion of vanilla and ate it. WOW. Just don't get addicted.
Find what works for you...but get in protein, okay? Take care and fight for your own health.