My 4 months plus baby suddenly become fuzzy before sleep. He used to drink his milk and dose off. But now, he keep opening his eyes even he is sleepy and cry. Is harder to smooth him to sleep even nap times. Diaper and food all done. And even he fall asleep he will suddenly cry like as if having a very bad nightmare that kind of cry. Any mummies encounter this? May I know how much milk does a 4 months plus baby drinking? I giving him 90 to 120ml. He is currently 7kg plus. I hope is normal...

If you feel it's not overstimulation or colic, then it could be that he's going through a period of development. I read somewhere that when babies are learning a new skill, it's like they have a voice in their head that cannot be turned off which repeats the steps to the skill. Thus, they are more irritable.

Your baby has developed a sleep association. The sudden loud cry is due to overtiredness. At 4 months their sleep patterns mature. I actually wrote an article on this. Feel free to check it out. http://sgsupernanny.com/4-month-sleep-regression-what-is-it-what-can-you-do-about-it/

Milk portion sounds normal. Could it be over stimulation before bedtime? young babies need time to wind down before bed. Do you have a sleep routine which you stick to?

Could it be colic ? does it happen at the same time of the day?

It could be overstimulation from the days activities.