Florist Question?? Is this weird or am i crazy???

Hi all! So my florist called me and said that the price of the florals I am using has gone up and that she needs $700 from me. I am using a lot of dried florals at my wedding and she has to get them shipped in I guess. It's not a large wedding, 120 max guest count. I paid her in full almost two weeks ago, which was a total payment of close to $7000. I knew I was going to spend a lot of my budget on flowers, that was the only decor I really wanted. However, is it normal for a florist to ask for more money after I have already signed a contract and made final payments? I really like my florist and I understand pricing can go up on flower market prices without notice, but I just wanted to know if anyone else had ever had this problem or if it is unusual.