Hay, mama, that's exciting na! Honestly, walang exact timeline, a few of us tried primrose oil din and some went into labor within days, pero iba pa rin talaga sa bawat mama, kaya just prepare your hospital bag na lang at stay comfortable nalang. The tightening and mild pain you're feeling is normal Braxton-Hicks, but since you're already 2-3cm dilated, best to keep your OB in the loop about any changes, lalo na if the pain gets stronger or regular na. You're so close na, mama, rest well and listen to your body!