Thank you for your query.
The pains you describe are pre labour pains.
is also very common during this time.
The thirst also is normal.
Higher amniotic fluid
is called polyhydramnios
and the causes are many like idiopathic ( no reason found ), chromosomal abnormalities in the baby, maternal diabetes
You should be evaluated for that.
With polyhydramnios you should be frequently evaluated by your doctor for preterm labour pains, as the distension and pressure predisposes to that.
Feeling chilly is not normal too, see your doctor for that.
You might be having a mild viral ' flu ' like episode.