Guidelines are merely that...guidelines. All parents eventually realize no two children develop the same, and their needs are all different. Your baby needs lots of cuddling, and if she's growing, will need those extra feedings. She may also be getting close to teething, and often babies need both cuddling and feedings to deal with that phase.
I personally think the cry it out method is bit much for babies. Once they're mobile, they naturally begin to ween themselves from nightfeedings and desiring to be held all the time. It's just the law of nature. Enjoy this time while you can. It's not spoiling. It's just a phase that will end too quickly in hindsight.
I think what may be the real issue here is unresolved feelings about leaving your child while you pursue career and school.
Unfortunately, for those of us who must work or choose to work, we then need to find someone we trust to proxy for us while we can't be with baby. While this is rational and a necessity, this reasoning totally flies in the face of maternal instinct and how mother's are wired. We're designed to "want" to be with our babies, and with this we're driven to be concerned with every aspect of our child's upbringing. This is the "rub" when it comes to career. You have to give up some of your "mamma-perks" if career is important. I suspect the underlying issue here is you're feeling a little threatend by the bond that has developed between Grandma and your daughter.
Reality is, they now have a routine that works. The baby trusts and knows grandma. They have bonded. Perhaps when you get home, there isn't a set routine, and it makes the baby agitated. Babies this young are slaves to routine. If she gets use to the pack n' play, that's where she'll want to sleep all the time. If you can't recreate this at home, she'll probably feel off kilter. This doesn't mean she's spoiled.
Your concerns are natural and understandable. And while a slight hint of "jealousy" might be at play here, I'm certain this is not be in the forefront of your mind as to what may be the real issue behind your question.
I know I've been there, when I worked and my mom helped out. I suspect, every experienced mom knows you can't really "spoil" a baby. And every mom knows deep down inside, they don't want to share the spotlight with anyone else when it comes to the affections of their children.
I say thank your mom profusely because she sounds wonderful. It's truly a blessing you have someone who loves your daughter that much, who is able to be there for the both of you. But on the same hand, I say be honest with yourself about what's really going on here.
Don't let jealously bubble only to rear its ugly head somewhere down the line, where you could hurt your mom's feelings and lose a great day care provider.
Give yourself the ability to confront those feelings. Do not feel guilty. It's natural to want your daughter to yourself. When you do have time with your daughter, make every moment a gem. Lastly, do something kind and special for mom. And if it doesn't ruffle your feathers too much, try using her methods at home.