Aw mama, normal yan sa pregnancy kaya don't worry too much! Yung ligaments mo (round ligaments) ay nag-stretch habang lumalaki ang baby, kaya may sharp or pulling pain especially sa bikini area kapag gumagalaw ka or nagbabago ng position, one of my mum friends said parang biglang tumatak sa kanya pag umuupo to standing, sobrang scary pero okay lang talaga. Try to move slowly, avoid sudden movements, at rest lang when you can, pero better pa rin i-mention to your OB next week, lalo na kung nag-change ang pattern or kung may bleeding or discharge, para peace of mind mo lang din and she can rule out anything else.