It's normal for kids to change their sleep patterns all the time. Mine is TEN and her sleep patterns still change somewhat, so I hate to tell you but....it's going to keep happening! She's still young enough for a lot of changes. She may be ready to have a shorter second nap or even to give up a second nap; some kids do go to one nap earlier than others. The nighttime eating may be a growth spurt and need for extra food, which will come and go many times in the future. As others noted, she may be starting to teethe (but does she seem to be in any pain?).
Like you, I did not do "cry it out." Babies this young do not yet realize that when you leave the room you do still exist; they think you basically vanish when you're not with them -- so no wonder they get distressed if you don't reappear. So I think crying it out only teaches them "If you are distressed, nobody's going to come to you because they aren't there any more." It doesn't teach them self-discipline at this age because they are not yet mentally developed enough to learn any. Go to her. She'll return to longer sleeps when the teeth come in, or the spurt is over (for now), or the naps adjust/end.
It will be tiring and you'll go through it again in other forms when she moves to a toddler bed and wants to experiment with getting up to find you...when she has night fears or nightmares...when she is school-age and has fears of fires at night etc.... I figure sleep changes are normal at all ages, you just have to adjust how you handle it and ensure the kid is healthy.