Ay mama, common yan especially sa early pregnancy dahil sa hormonal changes at blood volume increase, pero since may kasama pang weakness, mas safe na i-check mo ito sa OB mo para sure lang, baka deficiency lang ng iron or something na kailangan i-address. A few of us pregnant friends namin experienced similar, pero iba-iba talaga ang reasons kaya really better na ma-assess ng doctor mo directly, lalo na at 6-7 weeks ka pa lang at important na lahat okay sa unang trimester. Malaki ang peace of mind pag alam mo na lahat normal lang! Take care of yourself and don't hesitate mag-call sa clinic mo.