I am new to crochet and have a crochet hook from a magazine. It is double ended- a different size at each end. But it doesn't say on it what sizes the ends are. How do I find out? Is there a gauge specially for crochet hooks as my knitting needle gauge doesn't work for crochet hooks- I tried a crochet hook that does have the size written on it in the same size hole for a knitting needle and it doesn't fit in. Or am I measuring incorrectly?