The carsalesman who can't be trusted

I purchased a car at renault hatfield I was helped by the guy called Hendrick, when I got to the garage first thing I told him was that I don't know anything about car sales hence this is my first car I really needed his guidance, he asked the budget I told him is 4000 excluding insurance. He showed the difference cars, I like Renault capture then he said I will qualify for the car because the installment started from 2900. He called the next day saying Wesbank approved me, some guys is coming to fetch me at work, when I got there he told me now I have to pay 4500 per month for Installment I said no I can't afford that. He convinced me to take the car then after I can go to wesbank and pump in 5000 Rands and the installment will go down to 4000, he said all his costumers had been doing that.to cut the story short I'm paying 6000 per month for the car excluding insurance when I add insurance I pay 7300 which is a lot for me my family and I can't even afford to live because I'm the only bread winner at home they are relying on me, because of the salesman whom was pushing bussiness for himself and took advantage of me he knew I did not know anything , when I called west bank they told me the installment can't be decreased I must take back the car to the dealership if I can't afford it, if I call Mr Hendrick he doesn't take my calls anymore , n when I went to finances at the dealership the lady who works there said there is nothing she can to I must talk to west bank,so ive been going back and fro not getting any help. The only option left for me is to take the car back, I'm concerned about the money that I need to pay for the car because the car is being used, where I'm I going to get that money from? What is going to happen with my credit records?I'm I going to be able to purchase another car I future because in need of a car? Im stressed and confused.