Recent iui and chance of being pregnant?

I went for iui last week and got my progesterone tested. My level was 28. I looked up and found that's the highest for normal women. Does that mean it is a good sign. I had 5 mature follicles and today I have been dry heaving. What does your progesterone tell you. The last time I went through this my progesterone was 16 and I had a bfn.