Wa'alaikumsalam sis! Okay so sakit celah kangkang tu biasanya bermula few hours before labour proper, tapi memang lama dan tak tentu, ada yang 12-24 jam, ada pulak yang lebih cepat especially if bukan first baby. A few of my mum friends yang dah beranak cakap the key is to walk around, take warm baths, and just try to stay calm, sebab rushing to hospital terlalu awal boleh buat boring je kan. Kalau air ketuban dah pecah atau kontraksi dah regular and strong every few minutes, barulah pergi hospital, jangan tunggu sangat! Best to call your midwife or doctor first sebab they know your situation better, they'll guide you on timing yang betul for you.