Baby movements

Just wondering what is normal for baby movements at almost 34 weeks. The last two days I have found that I am not feeling a lot. My dr said that all they are looking for are 6 in 2 hours twice a day. However I feel like over the last 2 days I am barley feeling that and to feel that I have to stop and really focus on it. The movements are not the same either. Very slight where before they were way more noticeable. Is this the norm as she gets bigger or should I be concerned?