Hey mama, headaches during pregnancy are pretty common dahil ng hormonal changes at stress, pero kung it's localized sa isang side lang for 5 days na, mas better na i-check mo with your OB para sure lang, could be tension, dehydration, or something they need to monitor. A few of my mum friends had similar experiences and it turned out okay, but yung doctor nila nag-recommend ng safe pain relief at proper hydration, kaya don't hesitate to call your clinic!