What I think happens is the pasta absorbs the fluids in my stomach and expands to fill up all the space, so it turns into a mass of pulp. I think that it actually grows in volume after I have eaten it. So all the tea I drink after the meal gets absorbed into the pasta while it is in my stomach.
The thing is I don't know if this is true. It is just a guess based on my observations of what pasta does. It could be possible that any food causes me to feel full if I just wait 30 minutes. Perhaps something else is happening, I don't know. I may never know.
I am grateful I have food to eat, many people in the world today are starving.