u/ButterscotchNo4892

I am working on the Seashore skirt by Kutovakika (https://www.ravelry.com/patterns/library/seashore-skirt-3). It's my first lace pattern.

Unfortunately, after knitting half of if I realised I might not have cast on the best size for me. I want to double-check gauge but I'm not sure about the stitches in lace. Every repetition has 18 stitches.

I must be doing something wrong because I believe my gauge is smaller than pattern, but when I calculate the circumference of the skirt, somehow that's also smaller! Math isn't mathing.

I hope the picture is clear enough but I can upload more if needed.