Pregnancy Symptoms

I'm 4 weeks 6 days with my second child, my son is going to be 6 in July. I was further along when I found out I was pregnant with him and seemed to have all the 'common' symptoms. This time around I wouldn't even know I was pregnant if I hadn't taken the test. I do have sore boobs and most recently haven't wanted to eat. When did everyone start having symptoms? Is it common to feel nothing this early? Thanks 😊