Uy, please go to your OB right away, ha, better safe than sorry lalo na 15 weeks ka na! Kahit "normal" lang yan minsan, kailangan i-check ng doctor mo para sure na lahat ay okay sa baby mo. A few of us moms experienced different kinds of pains during pregnancy, pero ang best talaga ay i-confirm with your doctor kung anong cause and kung okay lang. Huwag maghintay pa, especially kung mahirap kang tumayo, that's your sign na kailangan ng professional check. Take care of yourself, mommy!