pregnancy symptoms?

Is it okay to not "feel pregnant" sometimes? For instance, I am 6 weeks pregnant and a first time mom and I've only had sore breasts one day and that was yesterday. It wasn't even the actual breast or nipple it seemed like the muscle behind my breast was sore. They feel normal today. Other than that I've had cramping and stomach aches with some nausea. But the sore breast are really weird because I thought that was supposed to be a major symptom everyone got?