Nah, don't worry. Expressing your feelings of love in a letter is definitely not a love letter. You're safe there, so just go on.
Mom's either sharp or a lucky guesser. My bet is on the former.
MMC's either sharp or a lucky guesser. My bet is on the latter.
Good going calling them monsters. That's like telling her she can't draw. You only do that if it's someone you know likes monsters.