Just a quick update,
I did some reserach and decided to try CIO. So, I tried CIO on my baby ONCE in the afternoon, she cried for 30-40mins on and off really loudly and there was no way she looked like she was going to sleep. After, I came in and finally carried her and almost cried myself, the poor girl was so tired from all the crying and she fell asleep in less than 5mins....my gut /maternal instinct tells me this method does not work for my girl and I stopped.
The next 2 days she suffered a hoarse voice from all that crying. I did more research and found out that ignoring baby cries has the reverse effect of them crying even more for some. And one should carry the baby as soon as they cry ( within 5 mins) to make them feel secure and confident.
True enough, I tried that out these days that once she crys, I pick her up and soothe her and she tends to cry less and also seems to sleep better and longer stretch. And when she wakes up now, she usually don't cry and will talk to herself or just quietly look at things or even smiles! ( if she is not hungry)

previously she will cry once awake!
I just want to share that if anyone should want to try CIO, please do it after 5months as well...
Below is some extract from what docs says:
"Some newborn babies don't like to be put down ever and cry the moment they leave their mother's arms, others are fine from day one," says Lyuba Konopasek, assistant professor of pediatrics a the New York-Presbyterian Weill Cornell Medical Center in New York City. In general, Konopasek says, a baby who is younger than 5 months old should not be left alone to cry for more than five minutes, at which point you need to pick him up and try to comfort him.