Orgasm

This might be TMI but I would really appreciate the help. So sometimes during sex and what not, my legs shake when he's on my clit. And I absolutely hate it. I've only came about 3 times and haven't since and we can't find "the spot" again. Why do my legs shake and why do I hate it so much?! I feel like that's "the spot" I just don't get why I hate it so much. I get so tense