Feeling pregnant. Then not?

Even before my missed period I knew I was pregnant and have had the symptoms to go with it...today I feel almost fine. No nausea, heartburn, exhaustion...my breast are still sore, I'm still a bit tired but didn't nap...I'm not bleeding or anything but I just don't feel it as much..almost 5 weeks today..is it normal to feel okay one day and not others?