It could be as simple as casting on more stitches between the tentacles maybe 40 or 50 instead of 30, depending on your yarn and head size. Never in a million years could I have imagined myself typing that.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog