Hi there. It is a shame how much of the burden of education is falling on the students and forcing them into debt.

In US there is no imprisonment for debts but you should really check with legal counsel in the UK and see about how this would be handled in UK. If not, consult the terms of the loan in the promissory note you signed if you have a copy.

You seem to have doubts if you want this degree or if you can finish, or if you will earn enough money to pay it back. It sounds like you are just starting, why not deal with the real concerns and separate them from the possibly unfounded anxiety before you start.