J.S.
J.,
It is not good to let a baby cry it out for so many reasons. As you saw, after the first time she woke up early and was upset. Is that normal behavior for her to wake from a nap that way? I doubt it. She went to sleep stressed and woke up stressed. Not good for a 7 month old.
The Cry It Out (CIO) method has many negative side effects both physical an emotional. Physically, the child gets stressed with a rise in blood pressure and a rise in the pressure in the head. The trauma to the larynx (vocal chords) is not healthy either - they aren't supposed to get hoarse. Emotionally, CIO is damaging as well - and sometimes the damage is hard to overcome. When you let a baby CIO you are teaching them one thing and one thing only: That you are NOT there when they NEED you. She is crying because she NEEDS you to be there with her; she is scared because she is not used to being by herself - she isn't supposed to be by herself. She needs the closeness she has had since she was born. She isn't yet old enough to have any wants...
Parents who do the CIO method usually do get babies to sleep by themselves - but not because the baby has learned how to self-soothe in a healthy manner - but because baby has given up - the realize that at some point during their day mom and dad will not meet their needs - so they give up. Is this healthy? No. Then many end up with a child who is fearful, clingy, insecure. This is NOT good.
Yes, there are those children who sleep alone very well and have no issues - but this is where you need to really look at the child's behavior. Crying to over 30 minutes is a clear sign that she is in deep distress and is in desperate need of YOU. Please keep that in mind.
Many people believe that there is some strong need to get the child into their own bed and to stop coddling them when they are little or else they will never be independent. Not true! I personally know of too many kids were co-slept until they were ready to transition into their own beds and did beautifully - they are healthy emotionally and physically, self-soothe just fine and are independent and self assured.
Self-soothing is not something you can teach by force - it is something that is learned when the child is ready - some get it earlier - some later. It's all good. I have 3 kids and they all learned to self soothe at various ages - it's about letting the child develop when s/he is ready - NOT when a book tells you.
Lastly, listen to your momma heart: If your momma heart is crying while she is - that is NOT right! Go get her!! You won't regret it - I promise. There few things more satisfying than being able to meet your baby's needs in such a special way as you have been. I encourage you to continue to enjoy the closeness you have shared with her and to enjoy the gift you have given her for her first 7 months. If you do, that gift will have long lasting and healthy effects for her and for you. As a parent who has done that, I can tell you it is a beautiful thing to have taken the time to enjoy my child's infancy, snuggling, nursing, co-sleeping and being able to let him transition to sleeping on his own when he was ready - it was seamless, there was no work involved, no crying, no struggles - it was healthy, and enjoyable all the way around.
I wish you much luck in your journey.
Warmly,
J.