Aiyo that reading is memang pelik sia! Usually after drinking the glucose drink it should go up lah, bukan turun, so 4.5 after is quite unusual. A few of my mum friends who went through GDM screening told me their numbers went way higher after the sweet drink, so your experience sounds off. I'd definitely message your doctor or clinic about this one, maybe ada technical issue with the reading or the test kena repeat. Don't stress too much yet, tapi better get them to check properly ja!