Hiya. 6 weeks is still pretty early to determine if possible stricture or problem. I'm 4 months and 2 weeks out and at 6 weeks, I was same as you. Ready brek had to be super thin and no lumpy soups. Anything thicker wouldn't go down. It's horrid. After 3 months of still being like that (they say allow 12 weeks) my bariatric team then looked at problems. The first being the mental issue. Had I put a mental block on solids, etc. at 4 months and 1 week I had an endoscopy and yes I had a stricture. This was last week Wednesday. Guess what? Since then I eat solids. Real food! Whoop whoop! And not been sick or got stuck once! Small portions, as expected, but now I am eating.
This may be the case for you, it may not. Other than your swallow test, which will confirm the bypass has worked, your bariatric team will allow some time before investigating structures, etc. you need ample time to heal alone. Everybody's body is unique. 12 weeks a good bench mark before worry can set in.
Look at my previous posts though, I know exactly how you feel. All I wanted was food. And could barely manage any.
Don't stress at this stage about protein in take. Your body has storage and trust me you'll have a few reserves to last a while.
Shirt term fixes, taste varieties that helped me at this stage:
Carrs Meltz crackers - diff flavours, literally melts on your mouth. Hence the name Carrs Meltz. Spread some laughing cow, or peanut butter (smooth) if you can stomach it. Goes down well and has protein.
Believe it or not at the stage you are now I started having cheesy wotsits. Not a long term fix but short term it gave me a taste variety and cos my general food intake was so low, the 95 calories in a multipack, didn't do harm. And gave me a feeling of indulgence.
Just be careful though long term wotsits are not a fix! Empty calories and zero goodness. But for now, they might offer you comfort.
Babybel cheese went down a treat for meal. As also melts. Small bites and breaks between. Even if you only manage half a one at first. It doesn't stick, and has protein. Have the other half later. Soon that will increase to a whole babybel and other cheeses. Even if possible stricture.
If you can handle milk, milky coffees, milky teas, latte's - get them down. Protein in the milk. At 6 weeks I couldn't stomach milk but at 8 weeks I could.
Low fat low sugar ambrosia custard.
Low sugar angel delight.
All this will help and give you variety.
Please though, these are short term solutions, some of these foods are 'slider' foods and not ideal long term. But until you are healed and possible investigation done, they will give comfort and not do any harm short term.
Also if you are like I was 2 LTR liquid at this stage seems near right impossible. Keep at it, it increases and becomes easier.
Read some of my previous posts, I had same /similar issues and got some awesome advice on here. That you can use now too.
Meanwhile, feel free to pm me if anything else I can help on, questions etc.
Stay strong x
Gasp! Essay over!