Hello girls. I have such a question, my child is 4.5 months old, since…

Hello girls. I have such a question, my child is 4.5 months old, since about 3 months old, she can suddenly cry and cry. It was like that I showed her a toy, she laughed, after a few days again show her the toy, she suddenly cried and cried (scared). Sometimes we go to the shopping center, she can cry there and cry, nervous. In the yard children played, the child watched and cried, suddenly, I read on the internet that it happens with kids, it's like self-defense, so I started worrying, is everything normal or should I go somewhere? We were seen by a neurologist before, everything was ok.