Daniel's Jewelers review: Diamond ring

I went to Daniels jewelers today looking for diamond rings and I feel like I was totally ripped off after getting home. I asked if they where real diamonds they said yes and the guy gave me a price for the ring 799.00 I left the store and came back to purchase the ring and a different person helped me and they told me it was 1000 and they gave it to me final price for 900 after she got off the phone. After getting home read the receipt and it said lab grown collection, no refunds or exchanges. I thought they sold me a natural mined diamond. This lab grown is worthless to me I feel like I paid 900 for trash. I'm really angry about this. I feel like I was scammed. I called a hour later after the purchase they said they will only exchange it. I would not have purchased it if they told me it was lab grown.