I want my money back

Hi, I discussed with the interior designer about my budget clearly. I sd im ok to pay a lil extra too. Aft she sent the quotation.. I paid money upfront n did not even negotiate thinking I may not get gd results if I compromise. Wen she came home first time, saw my home n said we can add carpet, cusions and curtains, lamps n lights. But wen I received the quotation..under the renovation of living room section I see only for four things such as curtains 9, two thread strips, 4 ottoman along with lights n lamps the cost says 16k. Next day she started asking me to pay total 16k but I paid her 10 k first day n next day 6k as she said she has to buy stuff. Now I'm v unhappy for the service she is providing. She bought the ottoman's 4 which she SD is buying from home center brand n each costs 2.5k but when I check the website of home center the actual total cost for 4 ottomans is 4680rs. Next, she SD will buy carpet 84 cm×1.5cm which is too small she purchased this and when I said please get this exchanged she's saying we can't exchange now. N the amount of that she has mentioned on the carpet as 1,785 but same type of carpet if I check In amazon I can easily buy a bigger size @ around 1290rs. Also she says she will not arrange the stuff but can guide us to arrange. However the gst is 18% in total, including the total amount of home paint which is 12,600rs. In total the invoice amount is 33,748 including 18%gst. I would like to pay for only paint and take back the rest of the amount asap.please suggest.