Like the little boy sings Open the eyes of my Lord...
Now...think logically.
If Jesus is the one holding Peter up then Jesus is the only one who could let him sink. Peter's fear is actually a chance for Jesus to give yet another lesson about something.
Water in the Bible is one of those "pithy" things. Heaven is literally said in Hebrew as "waters of waters"
Jewish tradition and beliefs understood water as different things.
Water from the sky is a gift from God. A blessing. Just like the Law of Moses. Many Psalms and other poems coorelate types of heaven sent water (like rain or dew) with laws of some kind. They can be as informal as a tradition or codified law as in the 613 laws of Moses or ceremonial law like hand washing.
Stored water (from rain) as in cisterns (hidden treasure) would often becomes brakish and undrinkable. Nothing good lives in stored water
Wells had an owner...as in the person who dug the well. Descendants only were allowed to drink from it as they were heirs. Again nothing lived in Wells...and sometimes they went bad poisoning everyone.
Springs and creeks and rivers had "living water" as it always flowed and moved.
Mikvehs (ceremonial bathing facilities for Levites before they could put on priestly robes and underclothes) had to be fed by a spring and flow...thus "living water".
A few homes had indoor water which were fed by springs....very expensive.
The Romans usually put a pagan statue at every water spring and said that their gods gave them the water...which really upset the ceremonially clean Jews who would refuse to drink.
After " man" was finished with water that God had given them it flowed to the sea...as in the Sea of Galilee. The sea was tehovm. Which had the meaning of abyss and chaos.
When the soles of a person's foot is placed on something it was a means for showing utter contempt for it. By walking on the
Sea of Galilee Jesus was showing the utter contempt He had for what they had done to what he had given them.
After this miracle Jesus went about "breaking" all of the Laws as they understood them. (Ignore chapter divisions). Jesus broke all law types from traditions to customs and even worked on the Sabbath.
So getting to Peter.
Peter had an argument with Paul in the book of Acts. Remember why?
Now considering the falling into the chaotic sea...wouldn't this "sinking" seem more of a prophesy of things to come than a failing to "tap into power" that really never was his to begin with?