Huge follicle CD 11

Today is CD 11, and I took clomid 100 mg on CD 5-9. I went for an ultrasound, and was told I have one large follicle size 27. I am taking ovidrel tonight and IUI on Wednesday morning. Is 27 too big, and will it even last until Wednesday? This is my second month of 100 mg clomid. Last month I had two follicles, sized 15 and 22, on CD 10. I didn't trigger or IUI last month.