Jangan worry sangat lah, fetal movement memang boleh berubah-ubah especially masa early pregnancy, sometimes it's strong, sometimes it's subtle depending on baby's position dan how busy you are jugak. Tapi since you noticed a change dari biasa, it's worth mentioning to your doctor during next checkup or call them sooner if you rasa anxious, just to get peace of mind! A few of my mum friends juga pernah experienced something similar dan doctor kata it's normal, but better safe than sorry kan.